Phone volume muting whilst sleeping

[Arjraj]

I have an Xperia Z3 Compact running Android 5.1.1 and whenever im listening to music and my phone goes to sleep while on the train the volume mutes. I then have to turn the volume back up again, which wakes it back up for about 2 mins before sleeping again.

I know I could just extend the time it takes before sleeping but that would just waste my battery even more.

Thanks in advance!

 

[Ralston18]

Very much a matter of the trade-off you are willing to make:

Listening time versus power conservation. Listening to music, which is what you require, needs volume which needs power which needs the battery.

So why is listening to music a waste of your battery? May be missing something in your post so please add details. Thanks.