2021 16" Macbook Pro M1 Max running Monterey with 4K screen connected through either docking station (yes this docking station supports 4K at 60 Hz) or HDMI port using HDMI cable, both ways I only get a 30 Hz refresh rate.

I changed out the "certified" HDMI cables with CableCreation 8K 48Gbps Ultra High Speed HDMI Cable 6.6ft, 4K120 8K 60 144Hz eARC HDR HDCP 2.2 2.3 Compatible with PS5 PS4 Series X Dolby Vision Roku TV 4K Sony LG Samsung TV RTX 3080 cables (which apparently are not certified), but it now works through the docking station showing 60 Hz, and allows me to switch to 50, 25 and 24 Hz and it works. So frustrating, but glad I am now able to get it to work!

Yes. New HDMI cables (Monoprice 8K Certified Braided Ultra High Speed HDMI 2.1 Cable - 3 Feet - Black | 48Gbps, Compatible with Sony PS 5, PS 5 Digital Edition, Xbox Series X, and Xbox Series S)

The link you sent says:

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Video Support

Simultaneously supports full native resolution on the built-in display at 1 billion colors and:

Up to two external displays with up to 6K resolution at 60Hz at over a billion colors (M1 Pro) or

Up to three external displays with up to 6K resolution and one external display with up to 4K resolution at 60Hz at over a billion colors (M1 Max)

Thunderbolt 4 digital video output

Native DisplayPort output over USB‑C

VGA, HDMI, DVI, and Thunderbolt 2 output supported using adapters (sold separately)

HDMI digital video output

Support for one display with up to 4K resolution at 60Hz

DVI output using HDMI to DVI Adapter (sold separately)

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My whole point is that using the HDMI port using an HDMI cable connected to my 4K monitor, it still only does 30 Hz.

When connected to two 4K dual monitors through a docking station which supports dual 4K at 60Hz, both monitors are only doing 30Hz.

Even though the Video Specification for my machine (2021 16" Macbook Pro M1 Max) says it should be able to support 3 4K at 60Hz, my point is that it is not doing for 1 when directly connected or 2 when connected through a supported docking station.

I would like to know how to fix this please. Citing the specification is not helpful when I am pointing out that it is not meeting the cited specification, which is why I am looking for a solution. I bought the machine on this spec, expecting it to be able to do dual 4K at 60Hz and it is not. Please let me know how to resolve rather than citing a specificiation.

Let's start with the simplest case. 2021 16" Macbook Pro M1 Max (with Three Thunderbolt 4 ports, running Monterey) directly connected via HDMI port on the Mac to a Dell Ultrasharp 32" UP3216Q Monitor, UHD 4k 3840 x 2160 at 60Hz, 16:9, 99.5% AdobeRGB, 100% REC709 and 87% DCI-P3, IPS, HDMI 2.0, DP 1.2.

When this is connected directly via HDMI cable to the HDMI port, it only reads at 30Hz.

When connected through a docking station (Macbook Pro Docking Station iVANKY 12 in 2 Docking Station 180W PD 4K HDMI USB C Docking Station Dual Monitor for MacBook Pro Air 2021 Thunderbolt 3 Dock 2HDMI 2.0, 18W PD, 6 USB, Ethernet SD/TF Audio) the same thing happens (only 30 Hz).

The other monitor is a HP W2408H 24-inch Widescreen LCD Monitor.

When these same monitors are connected through the same docking station to my 2019 Macbook Pro (Intel chip with Four Thunderbolt 3 ports) running Catalina 10.15.7, I am able to get 60 Hz on both monitors.

I just installed new HDMI cables (Monoprice 8K Certified Braided Ultra High Speed HDMI 2.1 Cable - 3 Feet - Black | 48Gbps, Compatible with Sony PS 5, PS 5 Digital Edition, Xbox Series X, and Xbox Series S) and it is still only getting 30 Hz on the 2021 16" Macbook Pro M1 Max, but gets 60 Hz on the 2019 13" Macbook Pro Intel Chip.

Any other suggestions??

I enabled HDMI 2.0 in the display's settings. I rebooted. That screen came back black, but on the System Preferences Display settings I now have a choice of 60Hz. At 60Hz, I get a black screen, when I set it to 30Hz I have a desktop again. Not sure what I am doing wrong :(.