Thanks FSD,
Like you, I'd have assumed that if video works, audio would too.
Audio tuning at our end is fine. I have no idea about the Israeli end, and I wouldn't even like to think about how to ask them to try it!
I think I will try to find someone else in the UK to start an audio conversation with, just to check that everything really is good from our end. At least that way we can narrow it down to the other end, and suggest that they find someone who understands computers to sort it out for them.
FFF
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