I'm using a ~3 year old Apple Magic Mouse (1st generation, removable AA batteries, part number: MB829LL/A), and it has started to give me brief disconnection warnings, but always automatically reconnects in .5 to 3 seconds or so. Here's a syslog snippet on gist.github.com. Clues so far:
- Started after upgrading to Yosemite / El Capitan (I only ran Yosemite for a week or so before upgrading to El Capitan)
- Only happens in cafes or on campus, i.e., where there are other devices around.
- Usually only ever disconnects as soon as I use the mouse after not using it for a few minutes. I.e., usually the mouse sits for several minutes and doesn't have any issues when I start to use it again; sometimes it has this disconnect aneurysm while actively using it.
Things I've tried so far:
- Removing the mouse, restarting, and pairing with it again via the Bluetooth PreferencePane.
- Ensuring the batteries are fresh / completely charged.
Based on #3 and what I gather from the logs, I'm guessing it's going into some sort of sleep / standby mode, and not always waking properly. Perhaps there's some OS X system setting that will let me turn this off or increase the period of time that counts as sleep-worthy inactivity?