Hi. I got a used gk 800rb, and it has a problem that i have narrowed down to an input jack. It seems that the jack has been "pulled down" by the weight of a cord. If i prop something like a roll of toilet paper under the cord, it is ok, but if i remove the leverage, the amp gets staticky and drops out. What i'm wondering is, if it is just a broken solder joint, how easy, and dangerous, is this to get to and fix. I am hesitant to open the amp, but Is it worth the money to take this to a repair shop, or is it something i can fix myself in five minutes? ( I have basic electronic and soldering experience.) thanks for any help.