its a 40 watt marshall vlavestate and when I turn it uop loud with the boost, it has a really terrible high pitch noise that is really loud and sharp. Its not the pickups are too close because it makes the noise even when Im as far away as possible. Is it the amp or my pickups? The amp also occasionaly kicks out.
ummmm.try turning down then amp then back up... i had that problem before..AMP prob...sometimes its the guitar.
it always does it no matter what and it has a kinda dirty sound to it even without the boost.
Use a different guitar and cord that you know doesn't make hum.

And try your guitar with a different cord as well.
Current Equipment
Jackson DXMG(Iommi)
Ibanez AEF30E
Peavey 6505+ 112
Iommi has work done to it.

On layaway:
Line 6 PODHD 300
I know its not the cord or guitar because ive used them on different amps
B.C. Rich Body Art Collection June Flesh Ring Warlock

Marshall 8040 Valvestate

1978 Peavey Classic VT 212 amp

All this 4 sale
Try moving your amp around and standing in different spots when you play. A lot of feedback issues are just to do with the acoustics of the room.
^Note: Probably sarcastic
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Few Agile 8-strings
Ormsby Hypemachine 2014 otw!!

Carvin X-100B
axe-fx II

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Quote by crisisinheaven
Deep*Kick. You have destroyed every concept of life I've ever had.
too much gain/speakers are pooping out. (i'm assuming it's an old amp).
Traynor YCV50 Blue
epi les paul w/ SD Alnico II pros
Dunlop Slash Wah
EH Deluxe Memory Boy
Moen Jimi Vibe
Danelectro Cool Cat Fuzz
Zvex Vexter Fuzz Factory
VHT 2x12 w/ V30's
It's sometimes the guitar, check out the input jack and resauter if ou need to.