Default [Q] how long we can record HD Video on Samsung focus

I can't record video vary long, less than 15 mins. If i record HD video, less than 10 mins. If i put the phone on charger for few mins ( like 5 mins ), and then start record HD video, in less than 2 mins, the phone will restart by itself, and whatever recorded lost.

Anybody has this problem? video recording is useless in Samsung focus for me.

I tried both with or without SD card. just updated to Mango last week.
Lumia 920

Nook HD+ CM11.0 Nightly

Nook Color CM11.0 Nightly

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