Hey guys,
I'm from Indonesia, finally found a way to solve the problems thread starter posted here.
Few weeks ago, I tried to flash my Lumia 920 059Q9X0 (APAC ID YELLOW) with various AU firmware from this website
http://forums.whirlpool.net.au/archive/2093342
Because my L920 product code hasn't get any 1314 update yet, so the first thing I did was upgrade my firmware with Australian unbranded 1314 firmware, hoped that latest firmware would solve the problem. But, no luck, the problem persisted and this time, the issues more easily came than the previous Indonesian unbranded 1308 firmware.
So, I downloaded all of the firmware at the first post and tried each one of them backward one at a time, I didn't notice that the 1249, 1308, and 1314 all have the same OS version: 8.0.10211.204. And the fact that all of those firmware didn't solve my problem, made me frustated and stopped me flash my L920 to the stock firmware.
But, this morning, being very impatient to wait for GDR2, I downloaded the stock firmware, crossed my fingers and
VOILAA I played Puzzle Craft, Jetpack Joy ride, and any other resource demanding apps and it's been more than 12 hours I have my freedom with this problems. I checked the OS version, it's 8.0.9903.10. I'm pretty confident with this OS version rather than the newest released for my product code.
I hope this helps. For the conclusion, the stock firmware OS version is: 8.0.9903.10 much more stable than OS version: 8.0.10211.204