Originally posted by RobA_Oz Hi soaptrail, and welcome to Pentax Forums.
I haven’t heard of this behaviour, before, but it doesn’t mean others haven’t.
You say that you’ve tried other lenses on the KP, but were any of them SDM lenses? If they were the older screw-drive lenses, then it sounds like a camera body problem (possibly the SDM power supply contacts?). If not, I can’t help any further.
I only have the one SDM drive lens. That would probably confirm if the lens or the camera is the issue if i had a second SDM lens. It is weird because despite the lag, i can still use the camera albeit it is painful and the focus was having issues when i heard the noises right before the lag started.
I bet it is the lens now that you ask.