Mesa DC-10 reverb adding lots of gain but no reverb

[mooktank]

My DC-10 is acting funny. The reverb has always been a little finicky; cutting in and out, getting distorted, etc. I figured I'd go ahead and change tubes since the reverb knob started acting like a gain boost or something without adding reverb. It happens with old and new tubes. Any idea what might have caused this?

 

[bhsbhswarp]

try the cable connections.May need to replace it.