5.1 Blasting Audio Issue — Please Help!

Hello! I am new to Jellyfin — my server on a decent spec Mac Mini, connected to a G-Drive storing the media. I am using the Infuse app as my client on an LG C2 display via AppleTV, with a Sonos soundbar and subwoofer connected via HDMI.

I was doing a hardware acceleration settings test this evening using a UHD version of Interstellar with 5.1 audio, it looked great, so I jumped ahead to the rocket launch sequence to test audio... I nearly shattered an eardrum. The down-conversion from 5.1 to my Sonos setup seems to have cranked the overall volume to unnaturally deafening levels. Has anyone experienced this? Any settings to check on in the client UI and within the server? I'm nervous to test it again tonight in fear of waking up the whole family. Seems like it's probably an Infuse issue?

Thank you!