I'm having problems with my V-Amp 2 with the output jack. I need to wiggle the chord in order for it to work and I also must put it in a vertical position. The soldering seems fine. Should I replace the output jack or check if there's dust? It was working fine not too long ago. I happen to be selling it and now I may not be able to since its not working right, even though it worked before I posted an ad. Any suggestions?