Trusty kernel lacks this fix: https://github.com/torvalds/linux/commits/master/drivers/gpu/drm/radeon/r600_hdmi.c
I saw a couple people with RV710 cards that are possibly experiencing this issue... https://bugs.launchpad.net/ubuntu/+bug/1312954
Trusty kernel lacks this fix: https:/ /github. com/torvalds/ linux/commits/ master/ drivers/ gpu/drm/ radeon/ r600_hdmi. c
I saw a couple people with RV710 cards that are possibly experiencing this issue... https:/ /bugs.launchpad .net/ubuntu/ +bug/1312954