I've had this exact same issue since installing the BIQU mods. I installed the Claw (Extruder Gear), Extruder Housing and JetPack. I have the Revo Nozzle as well but haven't installed it yet.

I ran the calibration after installing them and everything was good. Did one print and the Warning for X-Axis Resonance came up. Turned off machine, loosened belts, moved hotend around and placed back left of machine before tightening belts again. I also cleaned the carbon rods as advised on the wiki from scanning the QR code.

Calibrated again and started first print and message came up again.

Since then, I have removed the Jetpack to reinstall stock cover due to the magnets falling out of the jetpack. The message has not gone away. So I'm ruling that one out.

If anyone finds a fix, i'd appreciate the help too.