I have an Ampeg B2R bass head that is frustrating me. I will be playing through it fine, but after some time (About 10 minutes) it will make a strange "windy" type of sound. It is intermittent, not constant...comes and goes. I talked to some people and they said that it could just be dusty connections. I tried blowing it out to no avail. Tried taking it apart to see any obvious wire issues (I am not proficient with this stuff). Saw no issues, blew out the inside, still making the noise. Any other ideas? Thanks in advance, ABP.