When a power meter doesn’t align with the others

Hi folks, I have a Cinch power meter that appears to be calibrated low. I have multiple power meter bikes (all cinch meters in fact) and a Tacx Neo — the other meters and the Tacx are all within 1-2% of each other. This one in particular is about 10% lower than the others. This remains true regardless of firmware version (I’ve tried a few) from both Easton/RF and their manufacturer Zwatt. I calibrate the zero-offset before each ride (head unit “calibration”). Other than reading low, the meter is very consistent, but it’s throwing off my ability to complete outdoor workouts successfully and gauge efforts.

I know some other meters can be offset/manually recalibrated to adjust for too high or too lower readings. That would be ideal here but it doesn’t seem to be an option with the meter firmware. Can a head unit accomplish this?

Any ideas on what to do here? I understand the product is now discontinued so I can’t warranty it, and the shop I purchased it from is pushing back since it appears to be operating normally.

This is an outdoor racing and training bike so power match isn’t helpful to my use case.