Hi Irmin

thanks for trying to help, here are the actual settings:

Under prefs:

What is :
the internal sample rate: 44100 Hz
host sample rate: 44100 Hz
buffer size: 256 samples

Do you have multicore rendering selected? Yes
CPU overload detection? activated
Max polyphonie: 48

PS: Fusion Drive should not affect Pianoteq at all as it runs in memory only
Ah, this is an important hint, the MacMini runs in general very smooth, so I give it another try.

I just loaded a little project, just 1 audio-track and Pianoteq, no crackles at all ...sic.
But then again two ours later ...: zack, there they are again, you simply can't trust it, if I knew it would help, I would buy  an M1.
Thanks again, any further ideas?

Your settings are fine.  I'd try turn off multicore rendering to see if it helps

I have a 2013 macbook air, 48k sample rate with a 128 sample buffer and it has no issues. Works fine with internal audio and my Focusrite 2i2
I run pianoteq standalone or in reaper, unfortunately I don't have logic so I don't know how that performs.

Obviously an M1 machine would be light years better then what you have (as long as all your plugins work). I don't think anyone on here with an M1 machine has issues with crackles.

Last question does it sound like a buffer issue (e.g. increase the sample buffer to 512 and see if it improves) or is the audio clipping(that can also cause crackles)?

thanks for trying to help, here are the actual settings:

Under prefs:

What is :
the internal sample rate: 44100 Hz
host sample rate: 44100 Hz
buffer size: 256 samples

Do you have multicore rendering selected? Yes
CPU overload detection? activated
Max polyphonie: 48

PS: Fusion Drive should not affect Pianoteq at all as it runs in memory only
Ah, this is an important hint, the MacMini runs in general very smooth, so I give it another try.

I just loaded a little project, just 1 audio-track and Pianoteq, no crackles at all ...sic.
But then again two ours later ...: zack, there they are again, you simply can't trust it, if I knew it would help, I would buy  an M1.
Thanks again, any further ideas?

What is :
the internal sample rate
host sample rate
buffer size

Do you have multicore rendering selected?
CPU overload detection?

PS: Fusion Drive should not affect Pianoteq at all as it runs in memory only

the headline says it all: I permanently recognize crackles on the following system:
Pianoteq Standard 7.5.4
Logic 10.7.1
MacMini 2014, 2.6 i5 dual, 8 GB, OSX 11.6

The indicator shows heavy CPU-load - only when using Pianoteq, the rest works fine even with several plug-ins and tracks. Reducing polyphonie brought no effect, all updates were performed.

Maybe the computer in general is too slow, although I thought till now, the Pianoteq Plug-In does not use much CPU-capacity. I think the reason for the trouble must be the machine itself, the only speciality on mine: it has a so-called "Fusion Drive", i.e. combination of Standard HD and SSD. As far as I know Apple built these drives only for a short period, maybe it caused problems?

My question: has anyone experienced similar problems with a fusion drive? Or can give me a hint what could cause the described problems? Any message welcome.

Thanks a lot and best wishes

Karl