This has just started in the last hour.
I have several recorded programmes going back several months.
I started watching a recent one and the screen just shows the word "synapse" in the centre, in lower-case white on a full black background, but the sound is there.
I tried playing several other recording (which have played successfully before) and they all show the same thing.
I have switched the box off and on again but the problem persists.
Before I do a full reset does anyone know what this could be, and what does "synapse" mean in this context? tia

Which Humax box?

Synapse is a service ......

Synapse TV brings together SimpleStream, S&T and Vision21(V21) to deliver a one-stop solution to integrate over the top internet video into digital broadcasting systems.

See http://www.s-and-t.com/news/complete...esat-consumers

Sorry, it's an HDR-Fox T2 500GB, not connected to the internet.

Presumably this is your HDR-FOX T2 and you have recently tried out one or more of the IPTV channels. These do not work on the HDR-FOX T2 and can cause the issue you describe. It is not limited to just the Synapse channel.

Yesterday I did a total power off from standy-by to clear this from an HDR-FOX T2 on 1.03.06 where it was doing this with the racing channel instead of the Synapse channel. It played recordings fine after that.
Was you power down a total power down or just to stand-by?

If that had not worked for me I was going to go to the hidden service menu and reset Cookies & DRM data.

No, the last time it was connected to the internet via wifi dongle was about 3 weeks ago and the dongle was removed then.
Yes, it was put in standby not a switch off at the back.
EDIT:
After doing this post I tried playing the recordings again and they worked!!
I didn't power it down, it just seems to have cured itself.
There was a recording in progress at the time which has now finished.
Very weird indeed!

"synapse" is the text in the MHEG holding screen for LCN 790.

I noticed a few days ago that my YouView box was no longer displaying the "Synapse" slide. This problem has been reported with Humax YouView boxes since the weekend. I suspect they changed it from a pure MHEG-5 format to MHEG-IC possibly with further instructions to connect to the servers.

Both the HD/R Fox T2 series and their YouView boxes are not MHEG-IC compliant and seem to have MHEG engines that seem actively hostile to it at times. Try working your way past either CBBC or BBC Three when they are just displaying the slide (ie after and before 7pm) YouView boxes stall briefly when using the programme up/down buttons. It is usually brief but detectable and does not always happen.

I had similar: a Synapse screen and BBC1 audio.

Fixed it by doing a rescan for channels, and deleted all those mickey-mouse internet channels which don't work anyway.