iPhone battery goes down really fast and heats up when playing from saved songs

[savagepopkov]

I'm using the latest version of Spotify and iOS. I also use bluetooth headphones and play offline.
First I thought it was a problem with my phone, but I've tried restoring my phone, and the battery still goes down.
Also, I was playing music through a playlist, and everything was fine. When I play from my saved songs, the battery starts going down 2% PER MINUTE and heats up.

[snbeall]

Same problem. Seems to be particularly bad when I Bluetooth connect to a Bluetooth audio receiver. Premium subscriber and running latest firmware. 

[savagepopkov]

The battery goes down fast for me even when I don't use a bluetooth device to play music

I tested it out by playing music with no volume from my phone, and the problem was still there