Egon, there is an issue with the LTE radio when it loses signal and then regains it.
It seems to occur only when the signal is lost for an extended period of time. Basically, the way I noticed it (and some others) was by commuting. I ride a subway train to work - after I get out, and the phone regains signal, sometimes it goes into this battery drain mode.
This only happens with LTE. If I disable LTE (by using a different APN that only connects to HSPA+), this issue goes away.
A bunch of folks from XDA also documented this issue, and we submitted it to HTC. We'll see if it gets resolved, but it's incredibly annoying. My current workaround is to put the phone into Airplane Mode when going into the subway. If I forget to do this, I have to restart the phone afterwards.
It seems to occur only when the signal is lost for an extended period of time. Basically, the way I noticed it (and some others) was by commuting. I ride a subway train to work - after I get out, and the phone regains signal, sometimes it goes into this battery drain mode.
This only happens with LTE. If I disable LTE (by using a different APN that only connects to HSPA+), this issue goes away.
A bunch of folks from XDA also documented this issue, and we submitted it to HTC. We'll see if it gets resolved, but it's incredibly annoying. My current workaround is to put the phone into Airplane Mode when going into the subway. If I forget to do this, I have to restart the phone afterwards.