Thanks farlukar - I reckon you've hit the nail on the head.
So it's an antiquated medium trying to be played on a state of the art browser (or something like that
At least now I know, I know!
And yes, I too HATE sites that INSIST you listen to their music - especially when I've got my own tunes of preference playing at the time.
The sound clash can be horrendous!
Next time I get that message, I'll check the source code for embedded nonsense and not worry about it too much.
It's my guess that QT version 6.5.1 was used (and embedded) during site build and it's demanding that version.
All makes sense now, thanks man.