I have my M8 stock and not rooted, updated to the last OTA.
Since I update it, I have some trouble with motion launch gesture activating the HTC voice command for calling.
The very first time it couldn't recognize any request. Supposing it could be related to the OTA update, I made an hard reset and now it can recognize my requests. After few time I incurred into another problem: when I try to launch voice dialing through motion launch gesture, HTC voice app. starts for a second and than it crushes without giving me the time to make the request.
Is it a known issue?