Strange issue: distortion on soft synth on headphones but not monitors

[Arlanda Airport]

Hi - I noticed a strange issue while recording last night in DP. I added an instrument track with Arturia Pigments 2 on it and noticed a cracking static noise on each preset when monitoring through headphones. When I listened to the synth on monitors, the static is not audible. The signal sounds normal. Further, I don’t hear any distortion when playing hardware keys in either headphones or monitors. Just when playing the plug-in. I’m using an 828es. Is there something I am overlooking in routing the plug-in synth? I’m running Catalina, latest versions of Arturia/MOTU software. Thought it could be a sample rate conflict but I would expect to hear the static on the monitors too. Thanks

[Gravity Jim]

Have you checked your gain staging on the offending channel(s)?

[mikehalloran]

Have you checked your gain staging on the offending channel(s)?

The next thing I'd check is buffer size.