How to fix refresh rate Issues on Dell monitors after Sonoma update

Well this is fun! Ever since Sonoma 14.3 I hadn't had many issues, I was silently hoping it was fixed. NOPE!

no settings have changed, and its back to disconnecting external drives, back to the Apple Thunderbolt Display not being recognized from sleep mode, and this... this is the new one!! My screensaver for both monitors (not 3rd party) both just keep randomly changing to whatever they want (no its not set on random) one usually sticks to what its supposed to be and the other just picks something else, then I will fix, then repeat, then I fix, then they swap and repeat. Im ready to be done with Sonoma already. I am holding out for the next update... I do not want to do a wipe clean. UGHHHHH

just here to LOL, that now Im seeing all of these news articles DO NOT UPDATE TO SONOMA 14.4! Apparently the issue alot of us are having is more wide spread plus more issues! Ironically, my issues have been much better with my Apple 27" Thunderbolt display staying connected to My 2020 27" iMac... Hopefully the next OS "just works" and we can stuff Sonoma in the "vista closet" and never look back! LOL

Same problem here on a MacBook Air M1 2020.

Using a Philips PHL 272PV 27" display.

Using refresh rate 60 or 50 Hz no signal, 30, 25 and 24 Hz no problem.

Same issue here after the upgrade. Macbook Pro 15(Intel)'' -> CalDigit TS3Plus -> Gigabyte MU28. Works fine in 24hz, black screen in >= 60hz.

Much of my monitor problems went away after replacing the cable with an apple cable 240W USB-C Charge Cable (2 m) - Apple. Doesn't mean this will help you but it could.

Tried that first. It doenst work. It was also charging via the USB C in Ventura. It is not now.

It worked after I shutdown my MBP and then powered on again. Just unplugging the external monitor did not work.

I have a Viewsonic VX1655 4K OLED and it only shows 60 Hz when HDR is on - otherwise it's 30 Hz tops. I reported it to Viewsonic.

M2 MBA with an external Dell 2k monitor that anytime I reboot the Mac the monitor doesn't come back. I have to unplug it and plug it back in to get it back.

I'm having the same issue. Upgraded to Sonoma today and it's not recognizing the LG monitor. Tried unplugging and restarting everything. Nothing is working.

I've never had a problem with this Mac or the cable until I upgraded to Sonoma so I'm going to say it's not the pin out of the cable.

i just got a new adapter. Problem solved. Good luck.

After my original post I updated to an M2 Macbook 14'' Max and this is no longer an issue. That could imply the issue is Sanoma on specific models only.

iturn2 it actually broke my webcam completely. It is no longer recognized at all. Nothing I have done has been able to bring it back.

brainstewn, I am starting to think Apple is trying to force us to buy there expensive monitors.