I purchased a Variax 500 just over a year ago so it's now out of warrenty.

After playing the guitar for 15-30min or so (especially noticable with distortion) there is a horrible crackling noise which starts off very subtle and gets progressively louder as time goes on to the point where it is louder than the guitar itself. On odd occasions the thick E string has stopped working entirely, but this is rare. I've tried reseating some of the connectors but I'm wondering if this is a symptom of a faulty piezo rather than a bad connection? Any ideas would be greatly appreciated.

I'm in the UK (Scunthorpe, Lincolnshire), so service centers are few and far between for Vaiax guitars.

Paul