I can't get any sound from my Fujitsu 42" Plasmavision after hooking up Apple TV via the HDMI input on the back of the TV. The picture is fine, however. I went into settings on the TV using the TV remote and checked the audio input for Video 5 (HDMI). I tried every audio input option, but still no sound. The Fujitsu manual said to use Audio 4 with HDMI, but no sound. I rebooted the Apple TV repeatedly. I tried every option on my Integra stereo tuner, to no avail either. Thanks.

SOURCE: Stuck on Standby, Fujitsu Plasmavision: Model pds4229e-b

If your television is going into standby when you are manually pressing the power button, that means your television is in safe mode. Your remote will not help you in most instances when this happens. If you heard a pop of some sort that is not good, if there was no noise then unplug the TV for an hour or so to let it reset it self. If that does not fix it you need some service work done on it.

SOURCE: Sharp Aquos 37" Audio Static Issue when watching DVDs

i have had to replace the hdmi input board on these units to fix them.

SOURCE: Hitachi 50V720 No sound with HDMI - no Component video inputs

Right now there seems to be many people with the same TV problems with sony and HDMI cables. Most of the solutions are resetting the TV and sony product. Try leaving your TV unplugged for a hour to let it reset itself.

SOURCE: Aquos LC-37D64U - I've got a Motorola DSR505

You have it hooked up right. I found something on page 26 of your manual. Look at the HDMI setup section. I think that maybe the problem there. It's an audio select option for input 5.
Let me know if it works.

SOURCE: Motorola DSR505 HDMI problem

Check to see if input 5 has a audio in source via RCA jacks. Many times manufactures will give you multi HDMI inputs but only one that has RCA jacks in case you are running a DVI/HDMI cable. If input 5 does not have those RCA jacks you will not have sound. I know this unit has multiple HDMI inputs. Look to see if any of the other HDMI inputs also have RCA jacks.
I hope this helps,
Skyassoc