I'm using the hdmi from my MBP retina to a Dell monitor (U3011), it syncs fine the monitor gives an error message that reads "Unsupported audio format. Please set the audio output on your audio player to PCM." if I go back to my old hdmi converter via the USB and audio connections the error won't show.
MacBook Pro with Retina display, OS X Mountain Lion
I would be grateful for any guidance with this -- the message pops up every few seconds, sits dead center of the screen, and really kills any chance of using this screen for serious work. I've been through all the menus of the screen and the support material at Dell trying to turn off audio or turn off this message, or even all messages; through the system preferences of the Mac trying to find a way to turn off audio output on the HDMI or change it to PCM, and can't find anything that will just let me just turn off this recurring message.
This is also happening to me it makes me CRAZY!!!
I verified that plugging headphones in to the Mac in an attempt to get it to stop sending audio to the screen does NOT work.
Found the solution! Use a Mini DisplayPort to DisplayPort cable, better resolution than the hdmi and only $18 on amazon. No errors and great display 🙂
Verified that this device http://www.monoprice.com/products/product.asp?c_id=104&cp_id=10428&cs_id=1042802 &p_id=8119&seq=1&format=2 also solves the problem using Display Port from the adapter to the Dell. Great 2560-pixel mode on the Dell.
I came to this forum originally trying to solve exactly this problem with my 2012-edition 15" MacBook Pro (+Retina) and my Dell u3011 monitor.
recabin is wrong! I know because I followed his suggestion, bought it and tried it, and it didn't fix the problem.
* If you use it to plug in HDMI, it doesn't filter out the audio signal.
* No matter which video port you use, you end up with constrained resolution, way below the maximum resolution of the u3011 (2560x1600). recabin says you get 2560 mode, but you don't, you get 2048x1280.
On another forum (https://discussions.apple.com/thread/2787822?start=0&tstart=0) I found a solution
This is a $5 displayport cable. With this, now, today, I am using my u3011 at full screen and without the annoying invalid-audio message.
I hope this can save someone a few dollars and some trouble. At the end of the day, this is a shared bug in both the Mac and the Dell monitor: the Mac should allow you to disable the audio signal or change its codec, and the Dell should allow you to refuse the audio or suppress the error message. Both companies are culpable.
One dollar solution: http://www.amazon.com/DisplayPort-32AWG-Cable-Plated-Connectors/dp/B0034X6SCY instead of buying the overpriced (Apple style) dual link
Getting invalid audio type when using hdmi from macbook pro
