I bought a MXR 10 band eq pedal from guitar center's used website, It got here today, I pluged it in and it started making weird high pitched scraping sounds. It sounds kinda like a record that someones scraping on a turn table. It's going through the front of the amp with no other pedals. It does it on both the clean, and overdrive channels on my Blackstar HT-5. It doesn't make the sound when bypassed. Whats wrong with it?

Guitars: Dean ML ATF3000, Schecter C-1 Black Market Custom
Amp: Blackstar HT-5
Pedals: MXR 10-band EQ, EHX Metal Muff
It's broken. Actually, I don't know enough to say if its just a bad connection inside. Have you tried different cables?
Quote by JD Close
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It's borked. I can't say exactly why, because it's not in front of me, and I can't look at the electronics, and since MXR uses board mount jacks, there's probably not a connection problem with the jacks.
Quote by diofan88
Naked with a bowl of cereal with headphones.
I have that pedal and yours is definitely broken.

Dude, if you look at Biz Rate, Guitar Center's rating isn't too hot (I haven't bought anything from them in 30 years because of a bad experience I had at one of their stores back in the early 1980's and other issues people I know had with them). If you gotta buy over the net used get it from American Musical Supply or Sweetwater. Neither charges sales tax, either.