Fuck your dock vendor or asus please.
asus 的人不好意思明白說我們就是要使用者買專用 dock。
My issue was now resolve. I change my dock then boom. it all works on all my tv(with sounds) and monitors(up to 4k resolution) without issues. Some docks/hubs are not compatible with ally I think.
ROG Ally - HDMI audio not (always) working