Hello. I also have similar issue with tvheadent. There is no tuner card in TV-Adapters list. I added my user to the video group by the command:
sudo gpasswd -a r video
and restarted, but that didn't changed anything.
Here is output of the starting tvheadent:
r@ngf:~$ tvheadend
[INFO]:v4l: /dev/video0: saa7134 Avermedia PCI pure analog (M135 PCI:0000:06:02.0 capabilities: 0x05010015
[INFO]:v4l: /dev/video0: Standard #0: 000000000000b000 NTSC, frameperiod: 1001/30000, 525 lines
[INFO]:v4l: /dev/video0: Standard #1: 0000000000001000 NTSC-M, frameperiod: 1001/30000, 525 lines
[INFO]:v4l: /dev/video0: Standard #2: 0000000000002000 NTSC-M-JP, frameperiod: 1001/30000, 525 lines
[INFO]:v4l: /dev/video0: Standard #3: 0000000000008000 NTSC-M-KR, frameperiod: 1001/30000, 525 lines
[INFO]:v4l: /dev/video0: Standard #4: 00000000000000ff PAL, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #5: 0000000000000007 PAL-BG, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #6: 0000000000000008 PAL-H, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #7: 0000000000000010 PAL-I, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #8: 00000000000000e0 PAL-DK, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #9: 0000000000000100 PAL-M, frameperiod: 1001/30000, 525 lines
[INFO]:v4l: /dev/video0: Standard #10: 0000000000000200 PAL-N, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #11: 0000000000000400 PAL-Nc, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #12: 0000000000000800 PAL-60, frameperiod: 1001/30000, 525 lines
[INFO]:v4l: /dev/video0: Standard #13: 0000000000ff0000 SECAM, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #14: 0000000000010000 SECAM-B, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #15: 0000000000040000 SECAM-G, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #16: 0000000000080000 SECAM-H, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #17: 0000000000320000 SECAM-DK, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #18: 0000000000400000 SECAM-L, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Standard #19: 0000000000800000 SECAM-Lc, frameperiod: 1/25, 625 lines
[INFO]:v4l: /dev/video0: Input #0: Television (Tuner), audio:0x1, tuner:0, standard:0000000000ffbfff,
[INFO]:v4l: /dev/video0: Input #1: Composite1 (Camera), audio:0x1, tuner:0, standard:0000000000ffbfff,
[INFO]:v4l: /dev/video0: Input #2: S-Video (Camera), audio:0x1, tuner:0, standard:0000000000ffbfff,
[INFO]:v4l: /dev/video0: Format #0: 8 bpp gray [GREY]
[INFO]:v4l: /dev/video0: Format #1: 15 bpp RGB, le [RGBO]
[INFO]:v4l: /dev/video0: Format #2: 15 bpp RGB, be [RGBQ]
[INFO]:v4l: /dev/video0: Format #3: 16 bpp RGB, le [RGBP]
[INFO]:v4l: /dev/video0: Format #4: 16 bpp RGB, be [RGBR]
[INFO]:v4l: /dev/video0: Format #5: 24 bpp RGB, le [BGR3]
[INFO]:v4l: /dev/video0: Format #6: 24 bpp RGB, be [RGB3]
[INFO]:v4l: /dev/video0: Format #7: 32 bpp RGB, le [BGR4]
[INFO]:v4l: /dev/video0: Format #8: 32 bpp RGB, be [RGB4]
[INFO]:v4l: /dev/video0: Format #9: 4:2:2 packed, YUYV [YUYV]
[INFO]:v4l: /dev/video0: Format #10: 4:2:2 packed, UYVY [UYVY]
[INFO]:v4l: /dev/video0: Format #11: 4:2:2 planar, Y-Cb-Cr [422P]
[INFO]:v4l: /dev/video0: Format #12: 4:2:0 planar, Y-Cb-Cr [YU12]
[INFO]:v4l: /dev/video0: Format #13: 4:2:0 planar, Y-Cb-Cr [YV12]
[WARNING]:v4l: /dev/video0: Device lacks MPEG encoder, device skipped
[INFO]:dvr: Creating new configuration ''
[WARNING]:dvr: Output directory for video recording is not yet configured for DVR configuration "". Defaulting to to "/home/r". This can be changed from the web user interface.
[INFO]:CSA: Using SSE2 128bit parallel descrambling
[NOTICE]:START: HTS Tvheadend version 2.12 started, running as PID:2196 UID:1000 GID:1000, settings located in '/home/r/.hts/tvheadend'
[INFO]:AVAHI: Service 'Tvheadend' successfully established.