Now I think about it, it is only during mythic+ that it happens. I knew there was one specific place but couldn’t recall.
It would have to get pretty bad for me to switch off arcane though. I’m not running high keys at the moment (4 is my highest so far I think) so it isn’t an issue. Yet. I could see it being an issue at higher keys.
Thankfully it hasn’t been an issue in raiding. Then I would have to consider switching.