Casting causes movement rubber band with a specific weapon

I has a unique staff which has a "Firebolt" skill and an additional "Ember Fusillade" skill that triggers on casting a spell.
When I use a spell/skill with the staff the character movement start to rubber band. I can still move but if i move for example 1 meter, i get thrown back 2/3-of that and it's quite annoying.
I saw on forums to try to uncheck the "Always attack without moving" box, but it was not checked for me and even if i check it nothing changes.
The weapon in question:
https://imgur.com/a/SCt6U3u

Holy shit, I've spent 2 hours trying trying to figure out why my game would stutter every time I casted a spell. Never imagined it was because of my weapon. Thank you so much for reporting this.