MBP making frequent alert sound when sleeping

[martens]

I recently got a MBP M4 Pro and put it where I had my MBA M1 previously: plugged in to USB-C monitor with USB hub. The hub has only one thing plugged into it, an Ethernet adapter. This is also the power source, via monitor power adapter. It's probably not enough watts to maintain battery level if MBP was doing something compute intensive, but I have yet to give it such a task.

When displays are on the sound does not fire; only at night when displays are sleeping (and I'm across the hall trying to sleep). I think this also happened with the MBA but maybe less frequently (I will try swapping them later to verify this).

I've checked Notifications and the setting is to not fire when the Mac is asleep. And only a couple of them are allowed to make sound.

I do get system alert about 'USB Devices Disabled on your Mac'. But Ethernet adapter is still working, and it's technically the only USB device. I suspect this is what is producing the sound, but if so, I cannot find a setting to mute it. And it fires every minute or two, so it's not clear this is actually what is producing sound. Any theories?

Alert sound is set to Boop (default) but this sound is more like Breeze.

My workaround is to mute the speaker, but wonder if someone has a way of doing it directly (e.g. setting some property with command line).

I hate notification sounds! it's impossible to know what the sound means if there are several notifications that produce them! I really only want sound for Time-sensitive alerts (calendar appointments etc) but there's no way to white-list, you have to go into each application notification setting and turn off sound.

It's like that Monty Python scene in Meaning of Life where there's a machine in the delivery room that goes 'bing' and nobody knows what its for.

 

[HobeSoundDarryl]

Pull the plug on the Ethernet connection for a night or two to confirm that the connection is the trigger?

Set up the schedule for Do Not Disturb between a certain time of night and the next morning? Or if that is too specific, just manual put it in DND until morning.

 

[martens]

DND does not have any effect, and neither does pulling out the ethernet adapter so that there are no USB accessories at all (other than the hub built in to the monitor). It still 'dings' when sleeping (but not when display is active).

It's easy enough to tap the mute key (assuming I remember to do it). I think if I plug a separate power adapter to the MBP that would take care of it too, but I like having just one thing to plug in.

At some point I'll find the little USB-C hub I have that I can plug both a separate power adapter and the monitor into so I still only have one thing to plug into the MBP, and also would need to clear a space in one of the now fully-occupied power strips for the power adapter. But I cannot find the hub.

 

[HobeSoundDarryl]

DND should silence it so that is odd.

Would you happen to have wifi turned on even though you are using Ethernet? If so try turning that off for a night. If there is absolutely no Internet-driven events because it still does it fully disconnected, then it has to be within the device or connected hardware… not notifications triggered by internet events like getting new mail or texts throughout the night.

Next, I would try to further isolate the device to rule out monitor, speakers, etc. Disconnect from monitor, etc so that it stands alone. Does it still make the sounds (through its own speakers) so you know for certain that it is within the Mac itself? Since you think it used to do it with the prior Mac, I’m suspicious of surrounding equipment like monitor, speakers, etc. If you make it an island unto itself for a night, you can isolate the origination within or outside of MB.

If that silences it, start adding one external hardware piece back at a time. Do attached speakers resume the sounds? Does the monitor? If it turns out it's accessories, see if you have options within the sound options of the accessories.

If it as fully disconnected island still makes the sound, can you trigger them during the day? On demand? If so, take it into an Apple Store and demonstrate the problem.

 

[martens]

Sound is coming from MBP internal speakers, not the monitor's, which are crap. WiFi connection is active as well. The sound happens whenever displays go to sleep.

I plugged a power adapter into one of the other USB-C ports, unmuted the speakers, and put it to Sleep.

I think that made it happy, but something just dinged, and I was not able to determine which of my Macs spoke up. I've changed one of them to have a different Alert sound and will see what happens....