I'experiencing the same problem.
Apple tv 3, LG 42LG3000 directly connected with HDMI. Cable tested between Xbox and same tv set, audio is ok.
So I exclude the possibility that HDMI cable or the TV set are the failure points.
I would say that the issue is in the apple tv 3 itself.
Any return from apple support would be appreciated. As of now, the product is useless and I cannot play any content from apple tv.
Thanks for your return. Sound effects and sound check are disabled. Moreover, if while playing I switch on/off them, nothing is changing on sound quality.
Not sure about treble, in my specific case bass are awful, speackers croak
The quality is much worse when media are played from iTunes respect from AirPlay
Certainly sounds like it's the AppleTV or something in its settings.
Always worth unpowering AppleTV for half a minute or so and restarting to give it a kick in the pants - sometimes cures no audio out.
Not clear if your saying it's worse via Airplay or Home Sharing from iTunes under Computers section - if it was a hardware fault you'd expect both to be equally as bad.
Can't see it being the HDMI cable - try a different HDMI input if you have one.
Does the TV have separate volume input correction for each HDMI socket? - check TV settings and maybe reset to default.
In Settings somewhere there's a setting for HDMI audio to set it to 12 bit or Auto or similar - try toggling that.
Last resort prior to taking it back to Apple would be to factory restore via itunes using a microUSB to USB cable.
My Apple tv3 also sounded different to my atv2. Not by much, but it sounded pinched and thin. The apple tv2 in my view sounded better than the original. This is all by using the apple tv linked to a library, NOT via airplay, which I dont like. I only got the atv3 for the 1080p video, but couldnt live with sound difference... I have a pretty decent set up and use it via toslink into a dac.
I returned mine for a refund. I thought it might be something to do with the higher video output. Anyway, I am sticking with the atv2 until I invest in a more sophisticated route.
Robert Mills! wrote:
This is all by using the apple tv linked to a library, NOT via airplay, which I dont like.
I agree about Airplay - I'm not keen on it.
Typical hi-fi isn't it - in theory the ATV 2/3 should sound similar but there are subtle forces at play in the digital domain that influence things.