Hey guys, so i'm having an issue with the fan in my Micromark 801. it intermittently starts making a somewhat loud buzz or whine after coming up to speed when i turn it on. it's not being caused by the fan blades hitting something as they spin. rather, it seems like a more perplexing sort of mechanical issue, possibly with the fan motor. if i jostle the amp a bit and blow into the fan i can sometimes stop it from happening, but not always. while making the sound the fan's RPMs are reduced considerably, which means that it's not only annoying but could cause the circuit board to overheat.
has anyone else had a problem like this? can an ordinary guy fix it? i'm not hopeful - this amp is definitely not meant to be opened up