Decklink mini monitor sluggish responsiveness

Hi all, I'm running Media Composer 8.4.4 with a decklink mini monitor and Blackmagic Desktop Video driver version 10.5.4

AVID seems to be very sluggish in this configuration, especially when entering trim mode, using trim mode with J-K-L keys, or dragging edits manually with the mouse. When I turn off the hardware video output, performance returns to normal, so it seems pretty clear that the decklink is the culprit.

I'm wondering if anyone has noticed this problem too, or has had success with a different driver version. I've played briefly with some other drivers versions, but many seem to crash Avid outright.

Thanks,
Matt