I tried this with a WiiM Pro and an echo studio but couldn’t get beyond 24/48 which it appears is as far as an echo device can go thereby limiting the Pro. I would expect/ hope that’s not limited if you’re just using Pro’s.
There were a few niggles in the WiiM app that WIiM say are down to the Alexa MRM stack - the WiiM app didn’t show song progress, and while you could stop playback, you couldn’t resume it. Track bitrate etc couldn’t be shown but that might come later. Given Alexa MRM needs to be initiated from the amazon music app, maybe that’s the single control point - I forgot to check where the Alexa app might fit in.
I already had the HD/UHD toggle on, but did have to manually switch that off for a Mini&Pro MRM group I had also set up.
I don’t know if using the WiiM app and its roadmap upcoming hi res multi room will fare better than Alexa MRM
