Macbook Air M1 - ext display problems

[cheeky_chops]

Missus has a new macbook air - as she uses her old 2015 model alot for PPT presentations and training clients, she went for the high spec 16gb etc with the 8 core GPU. I did read some news about "new architechture/compatability" so we waited until MS Office was released natively, ordered and shes had it about a month now

She used the Apple migration tools to copy old>new laptop. We didnt notice the problems as she wasnt using a ext screen for a few weeks - i got her a external UBSC > HDMI connector and it worked but sometimes the ext screens can flicker, not connect, go off/on or have wavey lines on ext screen. Once issues start its a reboot, even then it only sometimes works, Ive tried the USBC into my new dell windows, even plugged into into my Android phone and the ext displays (3 TVs or a dell monitor) work no problem

Apple support sent her some instructions to run in safe mode (no diff) then to reinstall the big sur OS, the apps were still available after?. Im a windows person so even launching an app is foreign to me. Not found much on google. I think its a driver issues, shes just installed Big sur latest updates but no change.

Any similar issues or advise appreciated before she rings Apple again

[hyphen]

Is it an official apple dongle? If not try that one.

[LeeM135i]

Have a M1 MacBook Pro and use a couple of different dongles, one is a USBC to HDMI and it works perfectly, the other is a Belkin USBC hub with HDMI, USBA, SD card and 10GB LAN connection the works well except......

The original plan was to stick the USBC hub to the back of my 32" monitor and plug in the HDMI and USBA webcam into the hub then use a 1m USBC extension cable so I only ran one cable from the monitor/webcam to the Mac. I also have a work windows computer and swap between them during the day depending on what I am doing and only having one cable to swap would be ideal.

The PC a HP Envy works with the extension cable no problem, the Mac is flaky at best. If I plug the hub straight into the Mac it works fine just not with the extension.

I wonder if the Mac is more choosy about the quality of the connection or the cable length / power over the cable?

For reference the hub I use is https://www.amazon.co.uk/gp/product/B07Q3HP6KQ/ref...

Other than this small annoyance it's been a great computer.

[Prak]

Not quite the same as you are describing but there have been some reports of problems with external displays on the new M1 kit :

https://www.theregister.com/2021/02/22/apple_start...