playing on stage

When I play with my band on the stage I have to low down distorsion because my guitar screams.the problem is that I dont like the sound when I low it! :mad:
please help me... :(
p.s. I have stratocaster with 3 singlecoils and amp marshall AVT275

It's called feedback... when you set-up your gear next time, try to move around and find a spot that doesn't feedback as bad. Or you can get something called a noise gate. Which basically cancels the signal when you're not playing. You should find your feedback spots during your soundcheck. Then you know where you can't go on stage.

You need a noise gate pedal, problem solved. Moving around o n stage to find a place where the elctric frequencies are just right is a real pain in the ass. Invest in the pedal, they cost next to squat on ebay.

Yeah dude, you need a noise gate, but also, dont stand with your pickups facing towards your amp, this tends to make the feedback much worse...another solution(tho it may not work 100%) would be to play with a humbucker equipped guitar or fit a seymour duncan rails pickup(any rails should do) into the neck position on your strat...these are like retrofit humbuckers that are the size of single coils...could help out...Noise gate is probably the best and cheapest way!

You could probably use an attenuator too. It'll lower the volume of your amp without taking away the drive from the distortion.
You don't need anything extensive... just a small unit with a dial on it.

All the suggestions listed are perfect, you could also check your leads shield as well. cheaper leads tend to break down quickly so have alook at it. Also are you using a mike? that tends to add to the problems. Distance from the amp is the real solution if you cant get a noise gate. If the venue you play is small then get the amp up high using crates to stakk it. that is a good help and gets the sound out better over the crowd so you can turn the gain down a little to kill the feedback.