My mid 2014 MacBook Pro—while generally working very well for it’s age—is annoying me a little for the past year.

There seems to be an issue with the USB power supply where it’s not providing enough power for a SSD attached via USB. This only happens after it went to sleep once, and only if a peripheral device demanding more power was attached before.

It goes like this: After restarting the laptop I’m attaching the SSD to the USB port on the left side of the MBP and it works fine. Then I put the laptop to sleep, wake it up again and the SSD is not getting mounted. I plug it into the port on the right side and it works.

Now if I put it to sleep and wake it up again the port on the right is also not providing enough power any more. If I test the one on the left side now it’s also still not working.

The only solution is—as so often—to restart.