F-100 combo woes

[ran_dizolph]

Hey all,

I've had my F-100 2X12 combo for about 2.5 years now (I bought it brand new), and absolutely LOVE my tone. I'm typically running my '57 les paul goldtop reissue thru it, nestled on top of a marshall 2x12 1936 cab. Sounds great.

However, I have had many issues in the past with this thing. It has been sent in for repair 4 times already.

The latest issue is a new one...it's making a really short-out-ish electrical noise, in all channels, no matter what volume.

I have tested all the preamp tubes, as well as the power tubes, and this doesn't seem to be the problem. Before I take this thing in AGAIN, does anyone have any insight as to what might be going on? This amplifier is treated very well, not beaten up, and it's not the power source because it does it wherever I play.

Thanks!

 

[ran_dizolph]

k...lemme try this from a different angle.

Has anyone noticed a large difference in Mesa performance when using different tube brands? Any suggestions on what works and what doesn't would be appreciated, along with any troubleshooting tips i may have missed to sort out what's going on!

Thanks !