Hi Roger,
The 3500 was less expensive than it's brother : the Beomaster 4500.(which I have)
Based on my experience, I would ask you :Is the glass panel secured? Loose at all?
My glass panel succumed to the passing of time, and came off completely.And what it did reveal was
all the programme buttons,which responded to a light touch and all worked perfectly.
Despite many attempts I couldn't put the glass panel back on,so it's off to the service centre.
(It's a common problem evidently).
Essentilally. the glass panel has to be located just above the buttons to respond to "touch control functions. "
Hope this helps
regards
Noel.