Marshall MG 100DFX Static Noise

[rhoneamv]

Hi everyone,

I have a Marshall MG 100 DFX that is making a loud noise (sounds like static) when I crank it and it doesn't stop even if I put all the knobs in zero. I have tried different speakers but it is the same. However, when I play through my headphones the amp is fine.

Any help on how to correct this issue will be much appreciated

Thank you

[soundguruman]

Could be a blown speaker, check that first...voice coil rubbing on magnet.
but if you pound on the top of the amp, with your hand, or tap on the circuit board, the crackle noise occurs?
probably clean all the jacks and controls, re-solder the circuit boards
it is sometimes helpful to tap on the board(s) in several places, with a chopstick or other non conductive tool...wiggle each component,
to narrow down where a cold solder connection is located.
OR could just be a dirty jack causing the problem. Try cleaning them all.

Cleaner: the recommended cleaner is Deoxit D-100, Deoxit G-100, Deoxit Fader Lube.
Using the wrong type of cleaner can render your amp FUBAR. Never trust a salesperson to recommend the correct type of cleaner for controls (moving parts), and jacks (including plastic jacks). VERIFY on the manufacturer's website, that the cleaner you are using is specifically made for the application. You have been warned.

[Jazz P Bass]

"Well I sprayed it with WD-40"
How many times have you heard that?

[soundguruman]

"Well I sprayed it with WD-40"
How many times have you heard that?

WD 40 is a solvent cleaner which will strip the lubrication out of the controls. I leaves a little dry lube behind, but not enough.
WD 40 conducts electricity, in other words, your insulation is bypassed. It can also burn.
Very bad idea.
This is the perfect example of what not to do.