i have a chance to buy a swr workingmans 160 with a goliath II 4 10 cab for $350. is this a good price? i have not seen any of these used so i don't know. i have played through it a love the way it sounds. it is in pretty good shape. the only thing is when i plug into the passive input it seems the conection is loose. i thought it might be my cable, but then i tried a new cable and it still does it. it will work fine, then all of a sudden it will cut out, then i wiggle the cord at the input and it crackels a bit and then works again. is this something i can fix myself or have fixed cheap?