Problem may be encoder related. Whet condition are the belts in? After belt replacement, for 10k rpm machine, need to run the M83 cycle to "sync" the belts. after running the cycle to where the degrees are within 10 between hi and lo range, then run M84 to store values. Be forewarned, the M83 cycle is buggy. You will receive alarms and more often then not, the cycle will not complete.