Strange stereo/mono issue since the last update?

Hello mates, sorry in advance for my bad english, i’m going to do my best.

I dont know if it is because i’ve updated my Isla (last update 2022) but i’m experiencing something really strange and inconcevable in my sound.
Indeed, i’m feeling that “mono sound” doesnt exist anymore, or not as a “real” mono sound. I’ve changed nothing about my external sound card, all the pan of the isla is set to center, and when i set any sample in mono and play it, i still feel a stereo stuff in my headphones.

I tried to set directly the mono fonction in the IN of my external sound card and the real mono sound is ok ! (but i dont want to work in mono only in this way…)

So, i tried to reinstal the previous driver and the problem still remains…

Does someone experience the same issue ? Any idea ? is there a way to reset all the ISLA in his factory configuration ? (that could solve my problem maybe)
Thank you for your help