Cheers - I'll look into that possibility.

Bimmernav also came back and suggested it could be the amp picking up interference and to try a different location. Interesting as they prewired it with only 6" of wire...

Sorry that you were struggling with the button. We had an employee who has now been replaced. Unfortunetly he did not pay too much attention to detail. Everything is back on track now. I appologize for the frustration, but glad everything was sorted out.