In case if you'd like to make some DIY dust covers for your Speakers or Studio monitors, here's a walkthrough video to do just that. My 90 years old friend actually helped me make the covers. He's the one who did the sewing and stuff. I documented and edited the footage pretty much.

He made a cut out for the back cable for my Focals. He did say that if your device has multiple connecters, then it wouldn't make sense to make any cut outs at all. You can just sew the corner lines in the back to a certain point and then leave the rest open. That way the back section of the cover will just drop on top of those cables/connectors.