Hi, Can I start a dispute after giving favorable feedback. I bought an amp on ebay and when I used it (half hour)all seemed fine. a week later used again and would switch off by itself at random intervals. I took it to reputable electronics store and the report says

Report:Located foreign object across Pre amp circuit( looks like could be

remains of a cockroach or similar), suspect this has damaged pre amp circuit

and possibly output stage too, requires repairs to be completed before full

extent of the fault will be known, starting est of 265

Given unit retails for around 649 repairs are not suggested"

The seller said it had been tested. The electronics guy said "remains or similar" had been their quite a while which leads me to think TESTED means switched on....O good the lights work. is it possible for dispute?