Though as the title says, I can't remember for sure, but this is a phenomenon that has been seen from about a year or two ago. (Maybe It doesn't seem as old as a "sound bug")
While moving from area to area by walking or riding, the moment the area switches, the character moves momentarily to another way regardless of the key input direction.
(Example of location : Silver Spring ⇔ Aslan Valley, Syrbal Pass ⇔ Sarlo, Coast of Opportunity ⇔ Xaviera, Limo Desert ⇔ Land of Malevolence, etc.)
Though I've listed a lot of just in case, but from the nature of the matter, it probably location doesn't matter.
By the way, in my case, charactor often move to the left for a moment.(I don't remember right or backward)
Regards