Bluetooth earpiece and bad battery life
I found an interesting phenomenon with my phone. I bought a cheap bluetooth earpiece (Emerson) from Walmart to use when I'm in the office. I usually keep the earpiece off, but turn it on to make a call. When I finish the call, I usually (but not always) turn it off. What I've found when I do this is that the battery will drain much faster afterwards. Normally, with very light use (just checking emails, etc), I will get about 2% battery drain per hour. If I use the bluetooth earpiece, I will suddenly bump up to over 10%/hour for several hours afterwards.
It is repeatable and seems relatively consistent.
I've been playing around with it and noticed a few things. If I place the phone on the charger (I have the wireless charger) after I am done with the call, then this rapid battery use goes back to normal. Of course, I can also restart the phone and everything will go back to normal as well.
The highest app usage comes from the Kernal and Android system. It doesn't seem that the bluetooth itself is causing any additional battery use (based on Gsam battery monitor). The Phone, Phone Radio and Held Awake parameter percentages in Gsam are relatively low when this happens. It seems like the highest use goes to Kernal and Android system. Maybe a bug?
Don't know if there is a real fix for this and anyway, it seems I can fix it by just putting the phone back onto the charger, but it's really odd behavior. I wonder if some of the people complaining about poor battery life are using their phone with a bluetooth earpiece and thus experiencing the same issue?