Why are my woofers pumping?

My short summary, so far.
Vinyl rips from my main rig, made on my DSD recorders, played back at my modest cottage system, are able to reproduce subsonic pumping. When I play digital including advanced digital at the cottage system - SACD - there is no such pumping. With vinyl yes, some pumping, varying with the record.
This seems very similar to my findings, regarding my main system at home.
The pumping seems to happen with the cart-arm combo regardless of the player (VPI vs Hanss) - although I have not checked this much.

My audio friend Eirik came around today and helped me tighten the housing of the spindle on the Hanss player. Luckily the needed 2.5 mm Umbraco driver was included in the set I had bought. So - what was the result? Pumping: no difference. It did not go away. Sound: maybe a tiny bit more relaxed, less tense, but this may be my imagination. Eirik brought along some fine-sounding records and we played tracks from the Mofi edition of Dylan's Another side, and from the reissued Grateful Dead Cornell 1977 box. They sounded very good, and neither he nor I could find any clear indication of too much rumble. But he did remark on the LOOKS - the visual (subsonic) pumping of the woofers especially between tracks. It does not look like that in my system, he said.

Dear @o_holter : Two question, how is conformed your system speakers and its frequency response? is a passive design or active? two subwoofers or none? well more than 2 questions and other one.

I posted before that could be a good test to try to borrows a full SS phonolinepreamp instead buklbs you are using. I think you have to have that test, is a must.

R.

Dear Raul, thanks!

1)
The speaker system is Audiokinesis, Dream Makers in front, plus LCS speakers firing towards the roof, in the back of the fronts.
Similar to this one (but in much nicer light wood):http://www.audiokinesis.com/dream-maker-lcs.htmlThe frequency response is down to 20hz or lower in the combined system, not sure. It goes deep, that's sure.
But if speaker energy into the room etc was the main culprit, I would NOT have woofer pumping on my vinyl recordings (made when the speakers were off) - and I have!
2 Borrow full SS phono pre - yes, good idea. But again, I wonder, if this would solve the mystery. If it was related to the phono pre, the pumping should appear, depending on the volume. But it doesn't. It only appears when the needle is in the groove. More or less, depending on the vinyl record. Usually - maybe always - in EXACT repeat, each turn of the record.

The pumping pattern seems to follow its own logic, different from the normal vibrations and excitations of the woofer. As stated above, it is less obvious within than between tracks. This evidence suggests that it does indeed relate to the cart - arm match - it has too low resonance, and picks up too much down-below vinyl excitations, for some tastes, or just "good enough" for other tastes. The whole system goes deep down.

We played Pink Floyd: Meddle, the intro number, with the hammering bass, and noticed that a bit of pumping was still there, but NOT in time with the bass notes, but repeating - like before - in a once per revolution pattern.

"The highlighted noise on the LP playback, approximately 7 Hz, is absent on the CD. By the way, the very low frequency noise was present on every LP I played for this test: from new pristine vinyl to older worn LPs with more clicks and crackles."
https://www.vinylengine.com/turntable_forum/viewtopic.php?f=18&t=99388