B44.1 slipper loosening on own

[gazhillAE]

Guys
Ive not had this problem before just wondering if anyone can help.

New b44.1 only done 3 meetings, all standard slipper parts other than spur replaced with a jconcepts silent spur and the plates are the hi torque ones.

I adjust the slipper on track before start and it's fine, by the time I've finished it's loosened off again! Don't get me wrong it's not loose enough not to give drive but from a standing start it slips its nads off for 4-6ft!

I've replaced the rubber inside the adjuster but still doing the same thing