Has anyone updated? Haven’t had a chance to since I’ve been at work. Really hope there’s a fix for this awful mess. 

There’s a whole thread about this here: 

Hi all,

Thank you for your continued discussion. We’re really happy to be able to tell you that today we’ll release an update that will include fixes to the issues that resulted from the 14.12 software update with Enhanced Clarity for Arc.In the 14.12 release, we made a change to Arc’s sound profile to improve dialogue clarity and the overall sound experience.  Since that update, some users whose configuration included a Sub have experienced two issues:

1. Users of Arc would find the same volume settings resulted in lower output volume. Whilst the maximum volume and bass capabilities were unchanged, volume settings in the lower regions resulted in a quieter sound than before the update
2. Users of Arc, Beam and Ray would find their Sub output is lower than desired after performing a new Trueplay tuning.

(Home theatre configurations without a Sub were unaffected, including standalone soundbars and those bonded with surrounds only)

With the 14.18 software update, both of these issues have been addressed, and the Enhanced Clarity for Arc adjustments are retained. There was a clear preference within our community for the previous volume settings, and these have been restored. This will be apparent immediately after updating to 14.18. The Trueplay issue has been fixed. Customers who experienced a lower Sub level after performing Trueplay after updating to 14.12 will need to update their systems and then perform a new Trueplay tuning in order to address these improvements in their system. Customers will hear a more powerful low end response, meaning any Sub level adjustments made after 14.12 should no longer be required.

I updated to 14.18 and now my dual sub with Arc setup is nearly without any sound from the subs. I turn the subs on and off and barely hear a difference. Fix it Sonos. This is nonsense. 

I suggest that you reboot SUB’s and ARC.