[Jackaudio] jack & Ableton - Windows

Hi people, I am writing because I am experiencing a strange issue. I had a setup with Jack PortAudio (& Jack Control) for Windows, i opened them before (as admin), then opened Ableton and SuperCollider (also as admin) to bridge audio from one software to another. I also start Jack PortAudio with the following commands (going from Jack PortAudio -> Properties -> Shortcut -> Target): "C:\Program Files (x86)\Jack\jackd.exe" -R -P95 -Xwinmme -S -d portaudio -d "ASIO::US-2x2 & US-4x4" -r44100 -p512 I have been playing with this set-up from Jan to mid of March. Now I reopened my projects and something is wrong with that: when I play the test sine tone from Ableton, I can hear a sort of a Ring Mod, that is clearly a block size problem. I tried to switch block sizes - and sample rates - (both in JackControl and in the 'target' line of Jack PortAudio) but the only moment the test tone was playing kind of normally was once with 256 block size. But that time I had experienced a big problem: the sine tone was full of small clicks as my cpu was not handling it (which is really strange cause I normally have quite strong performances). So I really do not know what to do, also because this project was intended for my degree, which is tomorrow, but I have to rehearse this afternoon. Thanks for your attention Hope y'all are safe Respectfully Giovanni