IOS 8.4 faster battery drain on iPhone6

After upgrading to ios 8.4 on my iphone6 I noticed a faster battery drain - I decided to restore my iPhone but the problem persists. I would say its about 10% faster battery drain.

When I look at the Battery Usage the new Music App only uses about 8% in last 24 hour and 13% the last 4 days - Could this be the problem?

The music app is not listed in the Background App Refresh list so I cant disable it?

Like to hear what the others has to say.....

I really hope they are going to focus on the battery life of the new iphone - its really the "biggest" problem I would say.