Stereo mode switches guitar to left only

I’ve recently purchased Nolly and GoJira, both awesome plugins, I use them in Logic Pro X and Reason. I’m recently finding the stereo mode is throwing the guitar sound to the left channel in headphones and monitors, this happens when I use either plugin in standalone mode also - I’m sure this didn’t happen until recently.
Is this a flakey U-PHORIA UMC204HD audio interface or have I inadvertently messed with a switch or setting to muck it up?, apparently drivers for the audio interface on a Mac aren’t a thing. Does anyone have any help or advice before I write my audio interface off? I’m running guitar into input 1 of the audio interface, connected to 2019 MacBook Pro running Logic Pro X on Big Sur, thanks!