No, there is a bug in the whole Z5 range of phone's to do with audio. I'll try to find the link again! I came across a notification from some guy doing a degree in computer science who's investigating it for XDA who's looking for bug reports. I also now think the battery drain has nothing to do with the chipset, or the screen! I think there's a failure in one of the service's. My battery dropped by 50% last night with no radio services enabled, SOT, or active apps. Google and a few other things are however in the sleep white list for the power management in order to alow my smartwatch 3 to work, which kind of makes me think that it could easily be one of them, and given that the Sony smartwatch 3 is having sudden unexpected battery drains [and Google is the one common denominator] it could be a problem with the latest Google Now app!