Advanced: USB hub draining battery and heating up when not charging anything

[Wasabi0523]

Hi, I have a 2023 MacBook Pro I keep upto date (so it's Sequoia now), and I use a USB hub that has a USBA 2.4Ghz mouse received, USBA RGB keyboard, and HDMI to monitor plugged in most of the time. I usually charge with magsafe separately. Question: Any idea why the USB hub is hot, and the battery dies way faster than it would when the laptop is solo? It doesn't seem to matter if the keyboard is lit or not, and the keyboard and HDMI plugs (plastic housing) seem to get warm too. Thoughts?
Any way to turn off the USB charging? I think a data connection would be enough to run the keyboard. Thanks.

 

[FreakinEurekan]

I assume you've verified that the battery life is as expected without the hub (and keyboard) connected? If not, do that first.

Assuming yes - get a USB-C to USB-A adapter and try the keyboard without the hub. If the battery still dies quickly, the hub isn't the reason for it; the keyboard is.

 

[Wasabi0523]

I assume you've verified that the battery life is as expected without the hub (and keyboard) connected? If not, do that first.

Assuming yes - get a USB-C to USB-A adapter and try the keyboard without the hub. If the battery still dies quickly, the hub isn't the reason for it; the keyboard is.

Thanks for the reply. The keyboard by itself doesn't eat power like the hub. Is it possible that it could think the HDMI wants power? I don't know what else to do since I really want the hub and Mac won't let you stop sending power through a port, as far as I can tell.

 

[NoBoMac]

Good chance the hub is the culprit, drawing power for itself.

For example, I have an Anker USB-C hub that draws 15W. Newer version of it draws 15W as well.

And the maximum input watts is 100W. Even though you connect a 140W charger, the hub only supports 100W input. Due to the hub will consume 15W, the real charging watts for the laptop is 85W.

 

[chown33]

The System Information app should be able to show the complete tree of connected USB devices, including how much power each one has requested.

System Information User Guide for Mac

In System Information on your Mac, create a system report.

support.apple.com

Is the hub powered, i.e. plugged into a working power adapter? Or is it drawing power from the Mac? USB ports from the Mac will typically negotiate an amount of current that the USB device can draw. I don't know what the hard limits might be on USB-C ports. Posting the USB tree and the power-draw at each node could reveal this.

Maybe the hub is malfunctioning. You don't state anything about it (name, age, etc.), nor whether you have other hubs you might temporarily use.

 

[eas]

All those things draw power and I wouldn't be surprised if none of them did anything to optimize USB power saving.

 

[FreakinEurekan]

Thanks for the reply. The keyboard by itself doesn't eat power like the hub. Is it possible that it could think the HDMI wants power? I don't know what else to do since I really want the hub and Mac won't let you stop sending power through a port, as far as I can tell.

The hub is the culprit ¯\_(ツ)_/¯ At least three options:

1. Do without the hub
2. Find a hub that doesn’t draw as much power
3. Work with the hub manufacturer to troubleshoot the issue