[sawdust]

hi i had a 50001 system in last week that was doing the same, what was wrong was the sled rails needed greaseing( use sillacone grease or as a last resort wd40 on a cotton bud) after that no problems also done the romeo mod on it so see if the laser is sticking on the rails it should be moveing freely some times on the older systems the white arm that runs on the worm drive wears on the v9-10 this can be lightly bent down to give it more grip (i do mean LIGHTLY)
hope it helps