That adapter incorporates a signal converter chip that allows the source port to send native DisplayPort because the HDMI conversion occurs within the adapter. You can ask CalDigit to confirm, but if that's the issue, then you'd need an active DisplayPort to HDMI adapter like this one. Typical DP to HDMI adapters/cables rely on the source port having that capability. In any case, based on your setup and observatinos, my guess is that the DP outputs on the CalDigit dock do not support "Dual Mode DisplayPort" and therefore do not support falling back to native HDMI signaling.
Mini dp to hdmi for macbook pro pro#
Based on your description, it sounds like you have the USB-C Pro Dock, which despite the name will use TB3 capabilities if the attached system supports it, but it's good to be specific about equipment models in situations like this. But you really wouldn't want to use VGA anyway since it's an analog signal, whereas everything else is digital, and therefore VGA will look noticeably worse than any other matt Fyi CalDigit makes more than one docking station. Not sure what you mean about trying a "VGA daisy chain" though.
Matt Fyi CalDigit makes more than one docking station.