Tvheadend

No it's not normal; it's usually zero. But 1 data error per minute is not very many errors. You need to give more details of your equipment and signal levels if you want help to understand what's going on.

Thanks for the report.
I have a Pi3 running buster with TV headend.
I also have a PCTV 292e USB T2 tuner device plugged into that same Pi3.

My signal is coming from an ariel on the roof, via Coax cable into the USB tuner device.

The stream is recorded to the matroska profile as specified in the TV headend recording options.

The stream is saved to a mounted folder on the Pi3, which is a mounted file from my NAS drive on the same network (via ethernet).

Do you know how I'd identify what the signal strength is like, I'm unsure how to do that.
Thanks again

Ah... I've used this command on the Pi

femon -H

and it shows the attached... 76%
Not sure if that's good enough, or a problem... any thoughts whether this is good enough?

Errors seem to be 0 when recording a non HD channel... I wonder perhaps whether a different ariel is needed to optimise for HD??

For anyone else coming across this with the same occasional errors... My errors have now disappeared. I was relocating the TVheadend server nearer to the comms cab. and had to cut and re do the end of the cable.... since then it's been perfect... I think whoever put the original cable end on did a lame job! ;-)