How do I resolve the issue of two OLED monitors not being detected by a newer MacBook Pro and macOS 26.2?

Hello,

I have made a post about this issue here: Dual 4k OLED Setup not working with Macbo… - Apple Community

I have the same issue on my M3 Pro MacBook Pro that you have reported with the exact same monitors. This has been an ongoing issue for me since macOS 15; Apple Support has confirmed that this is a bug they are looking into. In my latest troubleshooting session with them we observed that there is an issue with the firmware correctly ID'ing multiple OLED displays and, to summarize, does not look for another display connection after the first monitor is connected.

There has, unfortunately, been no fix reported as of yet. Everything in my troubleshooting has been confirmed by Apple Support to be 'kosher' in terms of recommended setup based on their documentation.

If you haven't already figured a workaround out for yourself, I list some things in my post that I have done to get both displays working at the same time. I would highly recommend that you create an Apple Support ticket if you have not already done so - more tickets means it gets more attention.

“How do I resolve the issue of two OLED monitors not being detected by a newer MacBook Pro and macOS 26.2?: […]These two monitors work flawlessly on my work MacBook M1 Max on Sequoia and of course works with my windows machine.[…]”

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Troubleshooting Monitor Connection:

Verify the Connection:

First off, see if the monitors are even seen: 

1. Hold Down: the Option key
2. Click: the Apple menu
3. Choose: System Information or System Report
4. Select: Graphics/Displays and USB from the list on the left
5. Look For: the monitors

that AW2725Q QD appear to be a 3840 by 2160 (4K) display with up to 10 bits/color capability, that can refresh at up to 240 Hz

connectivity includes:

2x HDMI 2.1

1x DisplayPort 1.4

Your MacBook Pro M4, even if the (plain) processor, supports up to two external displays. (But likely not at the maximum refresh rates the displays support.)

The cables or cable/adapters required for recent macOS are extremely sensitive to ANY data errors, and therefore it is prudent to use cables that are certified and no longer than ONE meter.

If using a discrete adapter, the USB-C portion (before the conversion electronics) cannot exceed one meter, and the DisplayPort portion (after the conversion electronics) can not exceed one meter.

re: HDMI

HDMI derived from USB-C is less capable than DisplayPort derived from USB-C. The next step up in HDMI speed required more bandwidth than a ThunderBolt port could produce, so Apple created a DIRECT HDMI port with higher data rates to support HDMI 2.1.

HDMI 2.1 requires certified ULTRA cables, and nothing less will suffice. HDMI uses higher voltage levels, so allowed cable lengths are slightly longer than for USB-C or DisplayPort.

<< I have also tried using the supplied HDMI cable >>

cables 'shipped in the box' are notorious for being "lowest bidder" cables.

Unless it has certification tags and is specified as ULTRA high speed, that cable would be good for a 720p TV set, and not much more.

<< I believe the cables are fine. >>

if your cables meet the parameters I suggested, then you can look elsewhere for the problem.

Otherwise, cables are know to cause subtle issues, and should be upgraded until they fit the descriptions above.