Ethercat random jitter fix

Another thing that comes to mind, do your servos have braking feature? The clunking and the resonance could be related to that if you do have brakes, possibly they are not being properly managed? I use braking on my Z servo drive, and if I lock it when idle I have resonance as well, that's the only thing that comes to mind, also it does make a noise when it engages more of a click than a clunk, just my brain went there...

no braking features.
noise, I'm not sure how to really tell if there was. the cables are all cat6.

Cat6 come in both shielded and unshielded, need look at the cable specs, also the heads have metal, and you can check continuity for shielding, other than that, sharing your configuration would maybe tell us more.

Record lcec.0.pll-err with halscope. Should stay low.

Hakan wrote:

Record lcec.0.pll-err with halscope. Should stay low.

as i said it bounces plus or minus 30000 or so

Haha read-check
Ten times more than I got, still only 30 mikroseconds.
Could be enough if you are close to the limit. But you shouldn't be, I guess. Are you?

Record position feedback and commanded position when the clunk happens.
There ought to be something.