I’m wondering if it’s too thick without raising the arm of the player a bit higher. It might be that there isn’t enough force on the stylus and making the records sound weird. Do you have an adjustable turntable? On mine you can raise the height and also the weight on the back of the arm. You need enough downward force to play it correctly but not so much you’re carving new grooves into your records lol.
Also did you remove the standard mat before putting the slipmat on?
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