Hi - I have a problem with my Mustang. I thought it was just the input jack, however, I am not entirely sure if it is and before I start messing around with it too much I want to ask some advice and see if I was correct. [br]Here is a link to a YouTube video which shows there's a hum when anything metal is touched on the guitar. There is some output when pickups are selected but it's not great. [br]https://youtu.be/y4DrumYTspg[br]Thanks in advance for any advice you can offer to diagnosing the problem. is it the pick up selectors, the pick ups themselves?