I have a ESP LTD B205SM fretless and would like some advice on a problem. The problem is that my top string (high C in this case) has almost no sustain or tone compared to the other strings. I have tried many things (and strings) to resolve this without success. It's come to the point where I need to upgrade it or part company with it. I'm wary of investing what might amount to a couple of hundred quid with no guarantee of success and was hoping for some views on advice one way or the other.