ATI HD HDMI kein Sound AV Receiver

Hi Community!

i have read some of the posts with this error but found no solution working for me so this is my prob:

notebook lenovo edge e520 connected thru HDMI with AV receiver onkyo tx nr 509 on panasonic flatscreen. till yesterday all works fine.

now there no more sound thru HDMI.
in the win7 sound settings the primary sounddevice is always the txnr 509.

if i directly connect the notebook with flatscreen the sound works! connect back with the av receiver sound is off!

another notebook for e.g hp envy 3000 works fine with the av receiver!

is it possible there is an prob with win7? all drivers are up to date activate and deactivate the sound device has not solved the problem.
try with other HDMI cables without effect...

i have no ideas what i can do to solve this problem only i clean reinstall all from factory settings. :/

has anyone an idea?

cheers

Try a "System Restore" back to a date when it did work properly. This MAY fix it.

System Restore can be accessed from Start/Programs/Accessories/System Tools.