Hi, i've just actived the setting to get that loud sound when the lap starts/i start the lap in order to sync external cams to the data. But this unfortunately isn't working.
I've tried that with sound completely on (every sound bar on full, no "do not disturb" mode or anything).
This don't works ...

I got it working now. Software-Encoding is one option, another (faster) way is to set "Overlay frame capacity" to 5 (other as mentioned only 0-3 possible) which works quite well without freezing.
The storage-permission was correctly asked by the app. Thanks for your help.

I am having problems using overlay export function on my Nexus 5X running Android N Prev 5.

I am moving footage from my Hero2 Plus to the /sdcard/Movies directoy in order to import them to the runs. The preview is working fine, but the export is stopping at somewhat 10-40%, app going unresponsive ...