My New WiiM Ultra setup

[adias]

 

[QuarryHunslet]

Ok, that doesn't explain why the audio would be affected though.

As I expected: no audible "thumb" with my Thorens

The Rega is powered by an external 24 volt AC Adaptor, and activated by the rocker switch underneath the plinth, so whether the Ultra is picking up interference from the switch, I don't know.

I am planning to try another one of my turntables tomorrow, to see if this does the same. This is an old Sony Direct Drive PS-LX5, from the early 1980s.

Unfortunately, I can't try my Linn Sondek LP12 from 1988, as it is in need of a repair, or replacement power supply.

 

[harkpabst]

The Rega is powered by an external 24 volt AC Adaptor, and activated by the rocker switch underneath the plinth, so whether the Ultra is picking up interference from the switch, I don't know.

That's a bit of a surprise to me, I had expected this to be one of the older 230 V units and I was expecting the thumb to be the result of a switching spark. No so likely with the 24 V version, I think.

Rega turntables have no electrical connection between the motor PCB and the tonearm. You could connect e.g. just the left channel and see if the thumb still comes from both speakers.

 

[QuarryHunslet]

That's a bit of a surprise to me, I had expected this to be one of the older 230 V units and I was expecting the thumb to be the result of a switching spark. No so likely with the 24 V version, I think.

Rega turntables have no electrical connection between the motor PCB and the tonearm. You could connect e.g. just the left channel and see if the thumb still comes from both speakers.

It's quite a new Rega, less than two years old. As mentioned previously, when I had it connected to my WiiM Amp via the Rega fono mini A2D, there was no noise when switching the turntable on or off.

I can't try your suggestion today, because my ultra has been disconnected, and I have gone back to basics by connecting a WiiM Pro to my new Aiyima A70 amplifier to evaluate things, as I wasn't happy with the sound of the Ultra, and A70 combination, and have come to the conclusion that there are a lot of awful sounding recordings on the popular streaming services.