HELP- Why primers would load sideways on a 550B

I'm doing a 1000 round plus run of 9mm on a 550B. Primers are Wolf SPP, brass is mixed commercial once fired wet cleaned with stainless steel media. I don't think it would matter but projectiles are 115 grain TMJ from American Reloading and powder is BE86.

After about a 1K rounds I started getting an occasional problem where the wolf primers would seem to be slightly canted in their little cup and the result would be the primer being loaded sideways. It started out being an occasional problem but seems to be increasing.

My general MO is about every 300 hundred rounds or so I clean out any brass shavings or powder spill from around the shell plate by either hitting it with some canned air or taking it apart and wiping everything off and putting it back together. I don't see anything in the primer holder that would be interfering with the SPP siting in there flush......

....any thing I might be missing on why this is happening and how to fix it?