Pitch problem. Help

The most common cause of pitch variations is from the spindle hole not being perfectly centered on the record.If you notice any side to side swaying of the tonearm during play, that's your culprit.It will usually be most noticeable with string and piano and greatest towards the end of a side.

It could be because the mains power at certain times is less than it should be i.e peak hour and subsequent draw on the power grid.After 11PM at night it will sound pretty good.Other times bad.You can try mains power conditioning to fix this.

also check to see that the motor pulley is secure to its shaft.If it's loose, a tiny drop of superglue will do the trick.

these days power sucks- Add a speed controller and get a strobe and a strobe disc to check rpm there are several such as VPI SDS also other inexpensive ones check Music direct or a-gon etc. I have the SDS which puts the magic back regardless of input current.

I've recently ordered a Clearaudio synchro to address this problem but you might want to also check into the other various speed controllers which are available, such as the Project Speed Box or Speed Box SE;
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"This tiny black box allows painless speed change between 33 and 45 rpm with the mere push of a button. But that's not all. This neat little box offers quartz-generated electronic speed regulation. In other words, the Speed Box isolates the attached turntable from line voltage fluctuations that can affect speed stability. The quartz oscillator boasts a speed stability of +/- .01%. The more upscale Speed Box SE offers speed stability ten times better than the Speed Box. If you think a fraction of a percent of speed variation wouldn't have much of an audible affect, you should hear what the diminutive Speed Box can do. I'll get to it later but it literally blew me away. I truly did not expect the degree of sonic mprovements that this little CDN$129 box delivered."
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6moons Speed Box review
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