Continuous magnetometer reading fails with battery at 38%

I noticed the following behaviour:

• set a listener using Puck.on("mag", lsnr)
  
• start magnetometer reporting with Puck.magOn(5)
  
• lsnr is called only about 5 times and no more
  
  

To be clear: Puck.magOff is not called anywhere in between.

This happened with Puck.getBatteryPercentage() at 38. After replacing the battery with a new one, it all works fine again.

I suppose this should be added to documentation, or handled on a lower level - e.g. throw an error from Puck.magOn when battery voltage is below some level...