External monitor cuts out on MacBook with Multiport Adapter I have a newer MacBook with only a USB-C port. I use an Apple USB-C Digital AV Multiport Adapter, and the HDMI output has worked in the past.

When hooked to my new ASUS monitor with an HDMI cable, the display cuts in and out. Changing the resolution makes no difference.

I have tried three different cables, including a known good one.

I tested the display with a PC over HDMI, and it worked flawlessly in multiple resolutions (over a cable I had previously tried with the Mac).

What's my next step?
I tried a new cable and it worked.

Apparently HDMI is very touchy. Try different cables from different vendors until the display is stable.