M1 mini issue with dual monitors

Question

Level 1

8 points

M1 mini issue with dual monitors

Recently was able to get an M1 Mini,16GB, 512SSD and upgrade to Sequoia then Tahoe. M1 is rated for dual monitors of up to 4K and 6K. My two are 2K Lenovo D221's that I have used for years on an i7 MacBook Pro with a Display Link adapter for one and the other through the Thunderbolt port. No problems with them ever. On the M1 though, the D221 through the USB-C port will intermittently refresh for a second and come back up without having even stoped anything that you were doing on that screen. The HDMI D221 has no issues. These are 2K monitors so well under the specs Apple says should be OK. Any ideas as to the cause of the problem? Between this and the way they have buggered up Mail, Energy and other functions I am going nuts on this thing. The D221 has refreshed twice while typing this. Thanks for any help that you can give.

Mac mini, macOS 10.15

Posted on Dec 18, 2025 12:01 PM

Reply

Answer 1

Dec 18, 2025 3:55 PM in response to bansu

Check that you are using a high-quality cable or adapter, that is no longer than about 3 feet (1 meter).

Recent versions of macOS are reportedly intolerant of display transmision errors, and reportedly will reduce resolution or even cut signal if they see them.

Reply

Answer 2

bansu Author

Level 1

8 points

Dec 19, 2025 10:53 AM in response to Servant of Cats

That was my first thought too but I checked on the cable specs and it is max range for USB-C. and only 3 feet in length. Oddly a friend who does coding suggested the same on quality but to use a 6b foot cable. Not sure if this is a Mini issue or the OS with all of the screwing up the coders have done to Sequoia and Tahoe. Mail is a joke as is the Music app, which use to show the metadata on internet radio stations but does not now, so to listen and get the data of band/song/etc..... I have to use VLC, so that means the stations haven't dropped it, Music has been neutered. Not fond of Sequoia and Tahoe and not a novice with Macs as have had them exclusively for 24 years in 02/2026 and have been through a lot of changes but these 2 seem to have neutered or gotten rid of things normal people use most frequently. Coders being coders and trying to show that they do something unique to keep their jobs and meanwhile kiling things a lot of people use and have for years.

Reply