Uneven forces while handling my t300. (issue)

[Takso]

This has been troubling for a while.What is basically happening is that my wheel(t300 rs gt) feels like its unevenly distributing the ffb forces. Its tougher to turn it to the right than it is to the left and there also seems to be a deadzone situated more degrees to the left and to the center.The wheel returned from the tm's repair facilities and for 1 week at arrival it seemed to be fine. Just around a day or 2 afterwards,right at startup, i felt the exact same feeling im having now, which btw occured to me with my older wheel as well(dfgt). This seems to be some issue that does not necessarily have to do with ffb being faulty as tm didnt note anything on the service paper ffb wise. This does not happen constantly though.There are some days that it feels linear.However, when it does happen It seems like i cant wrap my head around it and find a solution to it. Any help would be greatly appreciated.

P.S: I'm also getting a notchy feeling a few degrees to the right from the center of the wheel.

 

[Takso]

Update:

After thorough investigation and testing i'm positive that ive figured out whats the problem here. By swapping the center points of the wheel 20 degrees to the left,which means that now the wheel is centered standing literally upsite down, the wheel is harder to turn to the left than to the right, which by itself means that now the uneven forces are distributed anti clockwise. That said and by swapping the center points of the wheel 20 degrees to the right later on (from the original default center point) i figured that there must be some mechanical issue going on, that doesnt have to do with the ffb.The ffb is simply amplifying the scale of the issue. So, at this point im thinking that the belt must be moving loose somewhere through the gears, or potentially even slipping slightly off track. A second exlanation i got is that the grease situated in the main motor shaft has partially faded some way or another.
On one hand im glad that theres nothing wrong with the software/firmware or the electronic side of things but on the other im frustrated with the build of this wheel base. I'm not sure what tm did to distribute and eliminate this issue but what i am sure about, is that it didnt last long and the issue is emerging back in the surface in a very short period of time.
If anyone has had the same issue and fixed it properly and for good, i'd really appreciate a quick guidance in this post.Last time i did try and do this, things didnt go as planned and the issue wasnt solved.(at least permanently that is)