I just tried this, connected a Boom to SN test, played some music and then removed the ethernet cable. After a while the display went dark as usual and I was able to go back into setup with the remote.

David: Can you reproduce?

Ping, David...

Steven notes that the specific original problem is that if you are playing at high volume, there is no way to turn it down.  It's far from clear to me what the right solution is.  Suggestions welcome!

I'll just mention the rant that came up due to a displayed message from the vfd regarding the loss of connection.  People get sensitive.

????
My son was playing some music in his room and had it turned it up a bit. Boom lost its wireless connection.  He came to me because he was unable to do anything the Boom either by the IR or UI.  Could not turn it down or off.  My 7 year old son could recognized that this is a major flaw in the product.

Felix speculates that the right thing to do might be to have the firmware be made aware that IR volume commands and knob turns should decrease the volume.  

Due to firmware size limits, including a visual feedback mechanism is probably prohibitive, but since the usage case is that the audio is already playing, the audio level should suffice as a level indicator.

Dean, what do you think of this?  Felix thinks it's do-able for 7.2, but we've gone for a long time without it.

If the connection is lost the player should go dark and respond to IR and buttons by waking up in setup.  This should be the current behavior for all IP3K-based products.

Is this not what's happening?

I've checked this with a Boom connected over wireless and wired and in both situations when the connection was lost Boom correctly showed the clock and was still controllable via front panel or IR as Dean suggested it should work.

Please reopen if you still see that after a connection loss the player does not react to IR or front panel.