I've downloaded the correct drivers & followed various instructions online, however as soon as I plug my Fireface 400 via firewire cable into my Mac (running 10.13.13) it immediately causes the computer to behave weirdly - the mouse won't track smoothly / becomes all drunk & glitchy! It runs totally fine again when I disconnect the soundcard.

Can anyone recommend a solution?

Interface: Fireface 400 (older model)
Mac: Macbook Pro running High Sierra (10.13.3)

Thanks,

Harry