Error 99 on 3DR compass calibration

have used this gps/compass previously with no problem. Tried a different mag cable but no luck. Get the red and blue lights and gps works great. same selections in MP (3Dr roll 180)as before but immediately get error 99 on compass 1 and 2 and only reads about 3 data points. Sits on mast away from metal, batteries, etc.

Have no idea what is up,

Thanks for yhour help

Hi could you explain how you resolved the issue?
I do have the same issue and could not find a solution for so far.

Thanks
Christopher