Try cutting strips of tape and sticking them thru the hole.. this makes the hole smaller and tighter so reduce the record slipping..

Increase the weight on the tone arm, or place a coin on the stylus to add pressure.

Take a cocktail size glass, preferably with a heavy base on it....turn it upsidedown and place it on the center of the record.
That should slove your problem. Let me know of your results. It's always worked for me.

if you pack them tightly into your record box they tend to flatten out over time

Wow, I've never heard of some of these technique's to fix a warp record.

There's only one solution, learn to use only the pitch slider and the platter edge (and a bit of the spindle) to find your beat match. This way you won't have to worry about super slippery warped records.

It's gonna be difficult but give it time, you'll get it in practice. Using primarily the pitch slider is more of a advanced stage of beatmixing.

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