Serious distortion from Rega RP1

Good option...I would contact your dealer or who ever the merchant involved is...possible to return RP1 as well?...Its a very entry level model and sounds like you have the upgrade bug...however upgrading without so living the issue is risky...I too believe its connections...grounding..just my .02...good luck

I wish I could return the Rega, but alas I'm well passed the warranty period. Part of the reason for a new cartridge is simply to have another "baseline" with which to isolate whatever technical problem is going on here, which is difficult to do when I only have one phono stage, one set of cables, one cartridge, etc. So if this new cartridge solves the problem that's great, but if not I've further narrowed the list of what could be going wrong (with the added benefit of owning a very good cartridge). Thanks to all of you for your continued help, and I'll keep you posted.

If you checked alignment et al on the turntable, its got to be electronic. A few years ago I had a similar issue crop up and traced it to a bad filter capacitor in the prepreamp.

@lousyreeds1
Hey, I’ve got the exact same problem with a used RP1 that I bought.
Distortion seems to come and go, most noticeable in the highs. It’s prominent in very busy passages in the songs. Happens on all my records, most of them are brand new as well.

I’m ordering in a gauge scale and a new stylus/cartridge and re-doing the whole thing for added measure. But seriously, what was the issue with yours? I’m very keen to know if you fixed it!