Sony revealed its lead cell phone lineup for 2015, and rather than the two variations that most were expecting, we got three - the Sony Xperia Z5, the Sony Xperia Z5 Compact, and the Sony Xperia Z5 Premium don’t have the necessary technical knowledge or skill to say that the 810 is the sole cause of the issue. But there is enough literature out there to suggest it may be the primary culprit.
Every device that has so far featured the 810 has been the subject of some bad press concerning user experiences with’over-heating’. One exception( again, so far) is the Oneplus Two, and that may be because they decided to clock the 810 lower at a max of 1.8ghz. Sony might have done well to have followed suit.