Guild Wars 2

I have Logitech G35 headset. Other games (DoW2, LoL, Bordelands 2) works fine.
I had a long break from GW2, but I think before it was fine. But now when I launched it and downloaded 29,000 files, dialogue scenes voices come only on my right headset earphone, same with some (as I registered, low) sounds from the game, which is terribly annoying and making normal playing unavailable to me.
Did anyone had similar problem or have idea how to fix it?
I have the newest drivers.

Have you changed or checked the setting on your system to see if it is configured to 5.1 surround sound, stereo speakers, headphones, etc? It can make difference and cause this problem with some games if you have it set incorrectly.
Screenshots below should help if you need them.

Win7:
Control Panel
Sound
Hit Configure button in the dialogue box.
Select the appropriate Stereo or Headphones option.
Also check your balance in the configure screens, or in the Properties button of your listed headset and check the Balance button there to ensure both left and right are equal.

Win XP:
Control Panel
Sounds and Audio Devices
Volume Tab
Lower “Speaker Settings” area
Advanced button
Then under the “Speaker Setup” dropdown, select “Stereo Headphones”.

If you are running special software that came with your G35, check to see if you have enabled the “Surround Sound” button. It may be conflicting with the settings you’ve chosen in the properties dialogue (XP) or configuration (7).

I hope this has helped. Please see the images below for more details if you need them.

Though some of listed options are not existing on my laptop (o.O), switching surround sound in G35 menu helped. Thank you very much.

Weird interesting things connected to last picture: I only have available 7.1 sound config.

Glad something I mentioned helped you out.
I figured it was more likely the G35 Surround Sound button, as I have seen that be the issue with other audio programs such as Xear3D and Audigy software.

I’ve seen only 7.1 available before, but I have not looked deeper into the reason for this, though it is probably also related to the reason for the G35 Surround Sound button bugging out.