Q: mb retina 12" bluetooth mouse disconnects intermittently

Today my Bluetooth acted up again after misbehaving frequently since I started having battery problems back in March.  My BT mouse and keyboard would lose connection intermittently.  It caused me to switch to a USB full Mac keyboard. Most of the time I had to reset the MB to resolve the issue.

After an OS update some time in July, BT did not cause problems.  Today was the first incident since then.

Actions taken to fix issue:

1. Turning mouse off / on: did not help (it often works)
2. Turning bluetooth off / on did not help (works sometimes if 1. does not work)
3. Reset system.  All is back to normal.

My configuration is MB Retina 12" early 2015.  Purchased 12/2015.

Bluetooth magic mouse.

Multiport AV adapter (MAVA) with the following peripherals:

• USBC used for power
• HDMI connected to external Dell monitor
• USB2 (A connector) connected to USB3 hub in Dell
  Connected to hub
  • USB3 external Seagate HD (self powered)
  • USB mac keyboard

I did have serious battery problems after starting in March.  Bluetooth issues and problems with the MAVA started at the same time.  In May the battery was replaced under warranty.  (The MAVA issue is being discussed in a separate thread).

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