Sorry for the delay in responding - I've been away this week. I tried this and it didn't help. IPTV channels (and I've tried feeds from a number of sources) stop recording randomly after anything from a few seconds to a few minutes. DVB-T2 channels using the same profile record fine.
Any more ideas?
EDIT - If it helps to diagnose the issue, the recording doesn't actually stop, the stream bandwidth just drops to 0 and no more video is recorded. There is nothing in the TVH log when this happens.
Dave