Audacity and UA Apollo x6 gives crackling distortion

Hi There,
Running Audacity 3.7.1. over my Windows-10 DAW with Universal Audio Apollo X6 interface.
Any DAW software works fine with my Apollo X6 except Audacity.
I use Studio One, Audition, Luna, ProTools etc.
Works flawless.

Can there be a driver problem? Asio against Universal Audio drivers?
My Apollo X6 runs over Thunderbolt 4.
I checked and played with buffersizes and other settings, crackling sound stays.

Would love to work with Audacity for the standard VO recordings.

Any hints are welcome.

Regards,

Hugo