Max2Play Home 2016 (en) › Forums › General Questions on Hardware and Max2Play Versions › Video streaming to a beamer via a 2nd m2p raspberry pi HDMI port? › Reply To: Video streaming to a beamer via a 2nd m2p raspberry pi HDMI port?
Firstly, congrats on finding your own solution.
Secondly, if you have not yet, you can add hardware volume control for shairport which is exactly what should fix your volume issue:
Optimizing Shairport’s Volume Control
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