When i took a SAIT night gunsmithing course one of the first things we were shown to lookout for was improper gear meshing on the outboard gearing that runs the power feed directional shaft & feed speed gearbox. A lathe was set up purposely to run noisily and then re-set to run smoothly....I was surprised by how noisy a gear train could be with a little bit of incorrect gear meshing.
While I have never had ant problem with power feed gearing , I did have a bunch of adjustments that had to be done in the headstock gearbox so gears mesh lined up with the lever detents (mine has levers, the one in the video here has those two 'arrowed" knobs). In my lathe, and i suspect yours will be the same as they originate from the same side of the ocean I think, I soon run into problems shifting gears and having the detents not place/lock the change-gears in the proper place. So, off came the gearbox cover and I discovered the problem immediately. The locking grub screws that lock the shift forks to the shaft from the outside levers couldn't be tightened enough to hold with much resistance it the gears didn't instantly line up . Two reasons I couldnt tighten them up enough ....first was constant oil splash kept the shafts very well lubed up and the second, mostly the culprit was the shift fork casting was not very beafy and I was very leery of stripping the threads on a "not very readily replaceable part". When i first removed the cover I could see that some of the gears, when i thought they were in position were actually only engaging corner-to-corner, just enough to drive the headstock.
The fix was really quite easy, and I suggest you have a look under the cover on your new lathe. I positioned the sliding change gear for each shift fork on a gear that it was supposed to run on, with the grub screw removed I center punched the shaft thru the screw hole. Now I manufacture a center-drilled drill guide that would slip fit into the screw hole to protect the threads from damage and drilled a small dimple into the shaft for the grub screw to embed into. That was 15 years ago and they have yet to come loose since then.