Bug when trying to record to audio track?

[CPLeu]

Hi, I'm having a very annoying bug when trying to record to an audio track. I have an external midi track sending midi through a midi cable from my soundcard to my synthesizer, then a seperate audio track receiving audio through a trs cable from the synthesizer into my soundcard. Normal stuff, everything works perfectly. Except when I try to record on the audio track, the bar at the top flashes red for a fraction of a second, and the time marker moves backwards a little, but then immediately stops itself. I've tried everything, recreating the audio track, changing settings, resetting i/o devices, closing and reopening logic, nothing works.

 

Also to note, if I try to record on any other kind of track (like a software instrument track) it records perfectly... One more thing, recently I recorded to an audio track from a live instrument using the same soundcard and trs cable and it worked fine, so maybe it's because of the synthesizer? I don't understand how that would be possible though.

 

Any advice would be hugely appreciated, thanks for your time. I'm on Mojave if it helps.

[triplets]

Could be that the synth is sending controller messages or is waiting for some Midi Time code.