Unfortunately I am in this exact same scenario, but with an M4 Pro MacBook Pro. Same exact monitors. I've tried CalDigit TS4 and CalDigit TS5 but I know it's independent of the dock because I can reproduce this directly from the laptop going to the monitors. Using HDMI alongside USB-C doesn't resolve it. The USB-C cords are quality cords, Thunderbolt 4 cords from Apple, as is the HDMI cable (I've tried multiple). The unfortunate workaround is a TWHT emulator: https://www.amazon.com/dp/B0DB7YDFD6 I have tried that before the HDMI cable directly from the laptop, and it works. My hope is that I can get this USB-C to HDMI adapter that is coming today and then put the TWHT on the end of that then the HDMI cable, so I can avoid a clunky scenario with multiple cords coming from the laptop. Here's the kicker: the M4 Pro is through work, but I also have a personal M2 Max MacBook Pro and it works perfectly fine there. I know the Max's have (and I might be saying this wrong) more dedicated graphics cores and maybe that results in dedicated pipelines per monitor which is why it doesn't get confused? (I'm almost certain I'm saying that wrong, I welcome correction here.) Very strangely, I must have done some series of things on Friday to incant this into working temporarily, because I was for a day able to get the M4 Pro MacBook Pro working through the dock, but I was sure it was a fluke that I wouldn't be able to reproduce (and I haven't) and as soon as I disconnected I'd probably not figure it out again... I know the issue and the workaround but I just wanted to add my voice to this thread to show that it's more widespread. I'm happy to file a bug if desired and use whatever utilities would help to gather info for that. I guess my only question I would have is this: I know it's not the OS or the kernel (right?), so is this something that could in theory be resolved with a firmware update at some point, or is this a pure hardware level issue that may be difficult to resolve?