Title pretty much sums up the problem.
From the control panel, the sound output has already been defaulted to the TV one.
Even though my laptop recognises the TV's audio device, it doesn't seem to be able to communicate with it. The following shows when I try to configure it.
My TV and the HDMI cable are fine. Nintendo Wii U (uses HDMI connection) works fine with them both.
I'm fairly certain the problem lies with my laptop. When I first bought it, it works fine, but now it doesn't transmit audio at all.
Windows 7 Home Premium x64, Laptop Model: Acer Aspire 5742
What could be the problem?