So a friend was messing around with my hartke combo and different speaker cabinets tonight. As a joke he plugged the speaker output from my amp into the instrument (line level) in of a guitar amp. I immediately smelled burning from my amp. I'm thinking its blown. What do you think? The amp is only a 25 watt combo but I've had it for a long time and I'm pretty attached to it. Should I plug it in and try it or will that make it worse? Is it worth repairing?