IVANKY 8K DisplayPort Cable 1.4, VESA Certified DP Cable 6.6ft (8K@60Hz, 4K@240Hz, 2K@240Hz)HBR3 Support 32.4Gbps, HDR, HDCP 2.2, FreeSync G-Sync, Braided Display Port for Gaming Monitor, Graphics, PC

Hey u/-thrun-, my setup sounds similar to yours. Was on a 2021 14" M1 Pro MBP connecting 2 ultrawide monitors @ 3440x1440 (main display at 120hz and the other at 60hz), plus other accessories, via TS4 using a single TB4 cable. FWIW I am using this cable as the included cable wasn't long enough for my setup: https://a.co/d/03clgUsz Main main monitor is hooked up via Display Port cable, and secondary monitor is hooked up via USB C to HDMI cable. I actually had issues with my MBP connection to both displays when I was on Sequoia, and updating to Tahoe fixed my issues. I'm currently on 26.5.1. My work MBP, which is 2024 16" M4 Pro MBP had Tahoe installed when I received it and has never had issues with the dock and 2 monitors. I found your thread as I purchased a 14" M5 MBP at Costco yesterday and was searching around to confirm if my setup would work. Costco has a great return policy, so I just opened it and set it up, which required me to update to Tahoe 26.5.1. Once the set up process completed the first thing I did was plug it into the dock and it worked just fine. Any luck on your end?