First check for or confirm you have clean wire. Then make sure that it is clean.
and then ... welp thats the idea. Also If you have a fresh roll you may want to try it as well. I watched one fellow fight with a MIG and when he changed to a new spool the trouble went away.
next step, Dan I take it you have a new liner?
Then if the rolls are slipping they may be dirty, run a tip of a pocket knife in the groove and see what happens.
If they are slipping and more tension causes a bird nest then it is time to look at the system starting with where the wire exits the rolls and goes into the gun. Strt setting and tightening everything. there are other things but try all that then ask again if needed.