I have a V6 box running TV360 and the optical audio output does not work, there is NO audio signal, coming from the V6 box. On my "old" TiVo box the optical output worked fine. I have checked the optical cable using another output device connected to the sound bar and it works fine. So the problem must be with the V6 TV box. Is there any "fix" for this.
First off, just to advise on terminology there's no such thing as a "V6 running TV360". When you converted your V6 into TV360, it stopped being a V6 - that refers to the TiVo-software which 360 is not.
Have you tried using the factory reset option on your 360, to eliminate a software gremlin? Use the option to retain recordings.
Edit: I responded to your post in the V6 forum before spotting that this was already an active thread in the TV360 section. I've now combined your posts into one.
Perhaps it would be useful to clarify which box you have, and what the problem is. The more info you give, the better the advice can be offered.
https://www.virginmedia.com/care/tv-fault/which-tv-box - a "V6 running TV360" is not a V6 anymore, but a TV360. Equally TiVo refers as much to the software as it does the older boxes.
In most cases you connect the TV to the TV box and use HDMI ARC to carry audio from the TV to the soundbar. In a minority of cases where the soundbar has both an HDMI input and an HDMI output (best) you connect the soundbar to the TV box and the box to the TV (for video passthrough). There is no benefit at all to using optical audio in preference to HDMI.
As far as I know the optical should work, other 360 users have posted about using it. I use HDMI and agree with Rodger_Gooner about it being superior also optical doesn't support Dolby Atmos.
Have you tried tried japitts advice and done a factory reset. Just select the option to keep your recordings.