Tektronix PS280 Repair

[rpcope1]

Hello everyone! I've got a Tektronix PS280 power supply I bought a while back at a surplus auction which has got a channel broken. This is a 2 adjustable channel + 1 5V rail power supply, so I've been ok just using one channel, but I would like to try to figure out how to fix it. The second channel will report close to 44V (this is a 0-30V PS) if you bring the current control above near zero, with absolutely no load on it. It does not appear to affect any of the other channels, so I usually just leave the current turned all the way down and ignore it. The only thing I've ever seen on the internet even addressing this problem is http://www.electronicspoint.com/tektronix-ps280-troubleshooting-problem-channel-output-t70457.html , which sounds a lot like my problem, however (this has been a couple of years), I think I tried to take the power transistor out and didn't notice anything funny about it. If it helps, I can also open it up and take pictures. I think this power supply is actually a rebadged GW Instek but I'm not sure which. Any help or input is highly appreciated!