Lately I’ve had an issue with my rMBP, that being the UI lagging. It begins to extremely lag when a few apps are open. Nothing taxing for the hardware, just Word, Safari, Photoshop, etc. It gets too laggy to the point where even using the OS is a pain. Has anyone expierenced this on their rMBP 2015? Mine is the Iris only model (Manufactured in 2018) Thanks!