Toshiba 3787db OSD issue

[roystonb]

Thanks Zeno!

I was wondering if it could be a dry solder joint somewhere, as it was working before it was moved!

If I call up teletext and then change volume via the remote, the OSD appears fine - its only when overlaying text or OSD over the source image, all inputs and tuner as well.

I have the service manual, but I'm struggling to find the circuit responsible for "mixing" text over image.
Happy to share the manual if it will help

Edit: Yes its a UK 37" model, a bit of a holy grail over here as it was the largest 4:3 CRT available over here so would like to get it fixed if possible.. there are very few CRT techs still working these days!