I get the same skipping/seeking playback issue in XBMC whether I view through PVR recordings (over htsp) or using NFS to a NAS.
Here are the logs from a htsp playback and also a NFS direct file payback.  Same crash
This is the log when I play a problematic recording using the "recording" PVR part in XBMC
> 22:35:20 T:3016988416  NOTICE: DVDPlayer: Opening: 
http://xxxxx:xxxxx@xxx.xxx.xxx.xxx:9981/dvrfile/124
> 22:35:20 T:3016988416 WARNING: CDVDMessageQueue(player)::Put MSGQ_NOT_INITIALIZED
> 22:35:20 T:2843880256  NOTICE: Thread CDVDPlayer start, auto delete: false
> 22:35:20 T:2843880256  NOTICE: Creating InputStream
> 22:35:20 T:2814774080  NOTICE: Thread CFileCache start, auto delete: false
> 22:35:20 T:2843880256  NOTICE: Creating Demuxer
> 22:35:21 T:2843880256  NOTICE: Opening video stream: 0 source: 256
> 22:35:21 T:2843880256  NOTICE: Creating video codec with codec id: 2
> 22:35:21 T:2843880256  NOTICE: CDVDVideoCodecFFmpeg::Open() Creating VDPAU(1440x1080, 2)
> 22:35:21 T:2843880256  NOTICE: vdp_device = 0x00000001 vdp_st = 0x00000000
> 22:35:21 T:2843880256  NOTICE: VDPAU Decoder capabilities:
> 22:35:21 T:2843880256  NOTICE: name          level macbs width height
> 22:35:21 T:2843880256  NOTICE: ------------------------------------
> 22:35:21 T:2843880256  NOTICE: MPEG1             0  8192  2048  2048
> 22:35:21 T:2843880256  NOTICE: MPEG2_SIMPLE      3  8192  2048  2048
> 22:35:21 T:2843880256  NOTICE: MPEG2_MAIN        3  8192  2048  2048
> 22:35:21 T:2843880256  NOTICE: H264_MAIN        41  8192  2048  2048
> 22:35:21 T:2843880256  NOTICE: H264_HIGH        41  8192  2048  2048
> 22:35:21 T:2843880256  NOTICE: VC1_SIMPLE        1  8190  2048  2048
> 22:35:21 T:2843880256  NOTICE: VC1_MAIN          2  8190  2048  2048
> 22:35:21 T:2843880256  NOTICE: VC1_ADVANCED      4  8190  2048  2048
> 22:35:21 T:2843880256  NOTICE: MPEG4_PART2_ASP   5  8192  2048  2048
> 22:35:21 T:2843880256  NOTICE: ------------------------------------
> 22:35:21 T:2843880256  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_NOISE_REDUCTION
> 22:35:21 T:2843880256  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_SHARPNESS
> 22:35:21 T:2843880256  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_DEINTERLACE_TEMPORAL
> 22:35:21 T:2843880256  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_DEINTERLACE_TEMPORAL_SPATIAL
> 22:35:21 T:2843880256  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_INVERSE_TELECINE
> 22:35:21 T:2843880256  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_HIGH_QUALITY_SCALING_L1
> 22:35:21 T:2843880256  NOTICE: CDVDVideoCodecFFmpeg::Open() Using codec: MPEG-1/2 video (VDPAU acceleration)
> 22:35:21 T:2793405248  NOTICE: Thread CVideoReferenceClock start, auto delete: false
> 22:35:21 T:2843880256  NOTICE: Creating video thread
> 22:35:21 T:2754173760  NOTICE: Thread CDVDPlayerVideo start, auto delete: false
> 22:35:21 T:2754173760  NOTICE: running thread: video_thread
> 22:35:21 T:2843880256  NOTICE: Opening audio stream: 1 source: 256
> 22:35:21 T:2843880256  NOTICE: Finding audio codec for: 86019
> 22:35:21 T:2843880256  NOTICE: Creating audio thread
> 22:35:21 T:2824211264  NOTICE: Thread CDVDPlayerAudio start, auto delete: false
> 22:35:21 T:2824211264  NOTICE: running thread: CDVDPlayerAudio::Process()
> 22:35:21 T:2824211264   ERROR: CDVDPlayerAudio::DecodeFrame - Decode Error. Skipping audio packet
> 22:35:21 T:2824211264  NOTICE: Creating audio device with codec id: 86019, channels: 5, sample rate: 48000, no pass-through
> 22:35:21 T:2754173760  NOTICE:  (VDPAU) screenWidth:1440 vidWidth:1440 surfaceWidth:1440
> 22:35:21 T:2754173760  NOTICE:  (VDPAU) screenHeight:1080 vidHeight:1080 surfaceHeight:1080
> 22:35:21 T:2762566464  NOTICE: Thread Vdpau Output Thread start, auto delete: false
> 22:35:21 T:2762566464  NOTICE: COutput::OnStartup: Output Thread created
> 22:35:21 T:2762566464  NOTICE: VDPAU::COutput::CreateGlxContext - created context
> 22:35:21 T:2762566464  NOTICE: VDPAU::COutput GL interop supported
> 22:35:21 T:2762566464  NOTICE: VDPAU::COutput: vdpau gl interop initialized
> 22:35:21 T:2719562560  NOTICE: Thread Vdpau Mixer Thread start, auto delete: false
> 22:35:21 T:2719562560  NOTICE: CMixer::OnStartup: Output Thread created
> 22:35:21 T:2719562560  NOTICE:  (VDPAU) Creating the video mixer
> 22:35:21 T:2762566464  NOTICE: VDPAU::COutput::InitBufferPool - Output Surface created
> 22:35:21 T:2762566464  NOTICE: Previous line repeats 8 times.
> 22:35:21 T:2762566464  NOTICE: VDPAU::COutput registered output surfaces
> 22:35:21 T:2754173760  NOTICE:  fps: 25.000000, pwidth: 1440, pheight: 1080, dwidth: 1440, dheight: 808
> 22:35:21 T:2754173760  NOTICE: Display resolution DESKTOP : 1920x1080 
 60.00 - Full Screen (12)
> 22:35:21 T:3016988416  NOTICE: Using GL_TEXTURE_2D
> 22:35:21 T:3016988416  NOTICE: GL: Using VDPAU render method
> 22:35:21 T:3016988416  NOTICE: GL: NPOT texture support detected
> 22:35:21 T:3016988416  NOTICE: GL: Using GL_ARB_pixel_buffer_object
> 22:35:22 T:2754173760 WARNING: CRenderManager::WaitForBuffer - timeout waiting for buffer
> 22:35:35 T:3016988416 WARNING: Previous line repeats 4 times.
> 22:35:35 T:3016988416  NOTICE: ----------- no buffer, out: 0, current: 0, display: 4
> 22:35:35 T:2824211264  NOTICE: Previous line repeats 4 times.
> 22:35:35 T:2824211264   ERROR: CDVDPlayerAudio::DecodeFrame - Decode Error. Skipping audio packet
> 22:35:35 T:2843880256  NOTICE: CDVDPlayer::OnExit()
> 22:35:35 T:2843880256  NOTICE: DVDPlayer: eof, waiting for queues to empty
> 22:35:35 T:2843880256  NOTICE: DVDPlayer: closing audio stream
> 22:35:35 T:2843880256  NOTICE: Closing audio stream
> 22:35:35 T:2843880256  NOTICE: CDVDMessageQueue(audio)::WaitUntilEmpty
> 22:35:35 T:2824211264 WARNING: CDVDMessageQueue(audio)::Get - asked for new data packet, with nothing available
> 22:35:35 T:2843880256  NOTICE: Waiting for audio thread to exit
> 22:35:35 T:2824211264  NOTICE: thread end: CDVDPlayerAudio::OnExit()
> 22:35:35 T:2843880256  NOTICE: Closing audio device
> 22:35:35 T:2843880256  NOTICE: Deleting audio codec
> 22:35:35 T:2843880256  NOTICE: DVDPlayer: closing video stream
> 22:35:35 T:2843880256  NOTICE: Closing video stream
> 22:35:35 T:2843880256  NOTICE: CDVDMessageQueue(video)::WaitUntilEmpty
> 22:35:35 T:2843880256  NOTICE: waiting for video thread to exit
> 22:35:35 T:2754173760   ERROR: Got MSGQ_ABORT or MSGO_IS_ERROR return true
> 22:35:35 T:2754173760  NOTICE: thread end: video_thread
> 22:35:35 T:2843880256  NOTICE: deleting video codec
> 22:35:35 T:2843880256  NOTICE: CVDPAU::Release pre-cleanup
> 22:35:35 T:2843880256  NOTICE: CDVDPlayer::OnExit() deleting demuxer
> 22:35:35 T:2843880256  NOTICE: CDVDPlayer::OnExit() deleting input stream
> 22:35:35 T:3016988416  NOTICE: ----------- no buffer, out: 0, current: 0, display: 4
> 22:35:36 T:3016988416  NOTICE: CDVDPlayer::CloseFile()
> 22:35:36 T:3016988416 WARNING: CDVDMessageQueue(player)::Put MSGQ_NOT_INITIALIZED
> 22:35:36 T:3016988416  NOTICE: DVDPlayer: waiting for threads to exit
> 22:35:36 T:3016988416  NOTICE: DVDPlayer: finished waiting
> 22:35:36 T:3016988416  NOTICE:  (VDPAU) Close
> 22:35:36 T:3016988416  NOTICE:  (VDPAU) FiniVDPAUOutput
> 22:35:36 T:2719562560  NOTICE: CMixer::OnExit: Output Thread terminated
> 22:35:36 T:2762566464  NOTICE: VDPAU::COutput: vdpau gl interop finished
> 22:35:36 T:2762566464  NOTICE: COutput::OnExit: Output Thread terminated
This is the log when I play the same recording over NFS from a NAS
> 22:35:56 T:3016988416  NOTICE: DVDPlayer: Opening: nfs://192.168.1.100/Multimedia/Recordings/MotoGP/MotoGP.2012-07-16.mpeg
> 22:35:56 T:3016988416 WARNING: CDVDMessageQueue(player)::Put MSGQ_NOT_INITIALIZED
> 22:35:56 T:2824211264  NOTICE: Thread CDVDPlayer start, auto delete: false
> 22:35:56 T:2824211264  NOTICE: Creating InputStream
> 22:35:56 T:2824211264  NOTICE: Creating Demuxer
> 22:35:56 T:2824211264  NOTICE: Opening video stream: 0 source: 256
> 22:35:56 T:2824211264  NOTICE: Creating video codec with codec id: 2
> 22:35:56 T:2824211264  NOTICE: CDVDVideoCodecFFmpeg::Open() Creating VDPAU(1440x1080, 2)
> 22:35:56 T:2824211264  NOTICE: vdp_device = 0x00000001 vdp_st = 0x00000000
> 22:35:56 T:2824211264  NOTICE: VDPAU Decoder capabilities:
> 22:35:56 T:2824211264  NOTICE: name          level macbs width height
> 22:35:56 T:2824211264  NOTICE: ------------------------------------
> 22:35:56 T:2824211264  NOTICE: MPEG1             0  8192  2048  2048
> 22:35:56 T:2824211264  NOTICE: MPEG2_SIMPLE      3  8192  2048  2048
> 22:35:56 T:2824211264  NOTICE: MPEG2_MAIN        3  8192  2048  2048
> 22:35:56 T:2824211264  NOTICE: H264_MAIN        41  8192  2048  2048
> 22:35:56 T:2824211264  NOTICE: H264_HIGH        41  8192  2048  2048
> 22:35:56 T:2824211264  NOTICE: VC1_SIMPLE        1  8190  2048  2048
> 22:35:56 T:2824211264  NOTICE: VC1_MAIN          2  8190  2048  2048
> 22:35:56 T:2824211264  NOTICE: VC1_ADVANCED      4  8190  2048  2048
> 22:35:56 T:2824211264  NOTICE: MPEG4_PART2_ASP   5  8192  2048  2048
> 22:35:56 T:2824211264  NOTICE: ------------------------------------
> 22:35:56 T:2824211264  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_NOISE_REDUCTION
> 22:35:56 T:2824211264  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_SHARPNESS
> 22:35:56 T:2824211264  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_DEINTERLACE_TEMPORAL
> 22:35:56 T:2824211264  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_DEINTERLACE_TEMPORAL_SPATIAL
> 22:35:56 T:2824211264  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_INVERSE_TELECINE
> 22:35:56 T:2824211264  NOTICE: Mixer feature: VDP_VIDEO_MIXER_FEATURE_HIGH_QUALITY_SCALING_L1
> 22:35:56 T:2824211264  NOTICE: CDVDVideoCodecFFmpeg::Open() Using codec: MPEG-1/2 video (VDPAU acceleration)
> 22:35:56 T:2762566464  NOTICE: Thread CVideoReferenceClock start, auto delete: false
> 22:35:56 T:2824211264  NOTICE: Creating video thread
> 22:35:56 T:2719562560  NOTICE: Thread CDVDPlayerVideo start, auto delete: false
> 22:35:56 T:2719562560  NOTICE: running thread: video_thread
> 22:35:56 T:2824211264  NOTICE: Opening audio stream: 1 source: 256
> 22:35:56 T:2824211264  NOTICE: Finding audio codec for: 86019
> 22:35:56 T:2824211264  NOTICE: Creating audio thread
> 22:35:56 T:2843880256  NOTICE: Thread CDVDPlayerAudio start, auto delete: false
> 22:35:56 T:2843880256  NOTICE: running thread: CDVDPlayerAudio::Process()
> 22:35:57 T:2843880256   ERROR: CDVDPlayerAudio::DecodeFrame - Decode Error. Skipping audio packet
> 22:35:57 T:2843880256  NOTICE: Creating audio device with codec id: 86019, channels: 5, sample rate: 48000, no pass-through
> 22:35:57 T:2719562560  NOTICE:  (VDPAU) screenWidth:1440 vidWidth:1440 surfaceWidth:1440
> 22:35:57 T:2719562560  NOTICE:  (VDPAU) screenHeight:1080 vidHeight:1080 surfaceHeight:1080
> 22:35:57 T:2785012544  NOTICE: Thread Vdpau Output Thread start, auto delete: false
> 22:35:57 T:2785012544  NOTICE: COutput::OnStartup: Output Thread created
> 22:35:57 T:2785012544  NOTICE: VDPAU::COutput::CreateGlxContext - created context
> 22:35:57 T:2785012544  NOTICE: VDPAU::COutput GL interop supported
> 22:35:57 T:2785012544  NOTICE: VDPAU::COutput: vdpau gl interop initialized
> 22:35:57 T:2754173760  NOTICE: Thread Vdpau Mixer Thread start, auto delete: false
> 22:35:57 T:2754173760  NOTICE: CMixer::OnStartup: Output Thread created
> 22:35:57 T:2754173760  NOTICE:  (VDPAU) Creating the video mixer
> 22:35:57 T:2785012544  NOTICE: VDPAU::COutput::InitBufferPool - Output Surface created
> 22:35:57 T:2785012544  NOTICE: Previous line repeats 8 times.
> 22:35:57 T:2785012544  NOTICE: VDPAU::COutput registered output surfaces
> 22:35:57 T:2719562560  NOTICE:  fps: 25.000000, pwidth: 1440, pheight: 1080, dwidth: 1440, dheight: 808
> 22:35:57 T:2719562560  NOTICE: Display resolution DESKTOP : 1920x1080 
60.00 - Full Screen (12)
> 22:35:57 T:3016988416  NOTICE: Using GL_TEXTURE_2D
> 22:35:57 T:3016988416  NOTICE: GL: Using VDPAU render method
> 22:35:57 T:3016988416  NOTICE: GL: NPOT texture support detected
> 22:35:57 T:3016988416  NOTICE: GL: Using GL_ARB_pixel_buffer_object
> 22:35:57 T:2719562560 WARNING: CRenderManager::WaitForBuffer - timeout waiting for buffer
> 22:36:11 T:2843880256 WARNING: Previous line repeats 3 times.
> 22:36:11 T:2843880256   ERROR: CDVDPlayerAudio::DecodeFrame - Decode Error. Skipping audio packet
> 22:36:11 T:2843880256 WARNING: CDVDMessageQueue(audio)::Get - asked for new data packet, with nothing available
> 22:36:11 T:3016988416  NOTICE: ----------- no buffer, out: 1, current: 1, display: 0
> 22:36:11 T:2843880256   ERROR: GetDelay - snd_pcm_delay, alsa error: -32 - Broken pipe
> 22:36:11 T:2824211264  NOTICE: CDVDPlayer::OnExit()
> 22:36:11 T:2824211264  NOTICE: DVDPlayer: eof, waiting for queues to empty
> 22:36:11 T:2824211264  NOTICE: DVDPlayer: closing audio stream
> 22:36:11 T:2824211264  NOTICE: Closing audio stream
> 22:36:11 T:2824211264  NOTICE: CDVDMessageQueue(audio)::WaitUntilEmpty
> 22:36:11 T:3016988416  NOTICE: ----------- no buffer, out: 1, current: 1, display: 0
> 22:36:11 T:2843880256  NOTICE: Previous line repeats 1 times.
> 22:36:11 T:2843880256  NOTICE: thread end: CDVDPlayerAudio::OnExit()
> 22:36:11 T:2824211264  NOTICE: Waiting for audio thread to exit
> 22:36:11 T:2824211264  NOTICE: Closing audio device
> 22:36:11 T:2824211264  NOTICE: Deleting audio codec
> 22:36:11 T:2824211264  NOTICE: DVDPlayer: closing video stream
> 22:36:11 T:2824211264  NOTICE: Closing video stream
> 22:36:11 T:2824211264  NOTICE: CDVDMessageQueue(video)::WaitUntilEmpty
> 22:36:11 T:2824211264  NOTICE: waiting for video thread to exit
> 22:36:11 T:2719562560   ERROR: Got MSGQ_ABORT or MSGO_IS_ERROR return true
> 22:36:11 T:2719562560  NOTICE: thread end: video_thread
> 22:36:11 T:2824211264  NOTICE: deleting video codec
> 22:36:11 T:2824211264  NOTICE: CVDPAU::Release pre-cleanup
> 22:36:11 T:2824211264  NOTICE: CDVDPlayer::OnExit() deleting demuxer
> 22:36:11 T:2824211264  NOTICE: CDVDPlayer::OnExit() deleting input stream
> 22:36:11 T:3016988416  NOTICE: ----------- no buffer, out: 1, current: 1, display: 0
> 22:36:11 T:2824211264  NOTICE: Thread Background Loader start, auto delete: false
> 22:36:11 T:3016988416  NOTICE: CDVDPlayer::CloseFile()
> 22:36:11 T:3016988416 WARNING: CDVDMessageQueue(player)::Put MSGQ_NOT_INITIALIZED
> 22:36:11 T:3016988416  NOTICE: DVDPlayer: waiting for threads to exit
> 22:36:11 T:3016988416  NOTICE: DVDPlayer: finished waiting
> 22:36:11 T:3016988416  NOTICE:  (VDPAU) Close
> 22:36:11 T:3016988416  NOTICE:  (VDPAU) FiniVDPAUOutput
> 22:36:11 T:2754173760  NOTICE: CMixer::OnExit: Output Thread terminated
> 22:36:11 T:2785012544  NOTICE: VDPAU::COutput: vdpau gl interop finished
> 22:36:11 T:2785012544  NOTICE: COutput::OnExit: Output Thread terminated