Radeon 6570 & Onkyo HT-R548

I've been thinking about your issues with the HDMI connections. First, let me ask for clarification on your statement that the audio breaks-up. Does the audio turn to static (kind of a hissing sound)? Does the audio crackle but keeps playing - never any time where there is no audio? Something else?

The reason I'm asking these questions is that HDMI transfers digital audio, so analog audio problems won't happen. However, the static sound could be the sound of bit errors in the audio stream which is usually followed by a brief period of no audio. Crackling however could be caused by having all the bits set close to full value for a long period of time. This drives recording engineers crazy since on analog recordings you could "push" the tape into overload, while with a digital recording you just get a really "ugly" sound.

So the source of your problem is different depending upon what the sound is like.

Also, how long are your cables? I assume they are all High Speed cables?

No, actually not really a hair puller. HDMI cables come in two varieties - standard speed and high speed. The high speed cables can handle all HDMI speeds (present and future planned) while standard speeds are only for 1080i and 720p speeds. Now most manufacturers will make sure their standard speed cables can do more than just 1080i and 720p. On the other hand some cables advertised as high speed will not handle the full HDMI high speed spec. That's because those cables were never actually certified to handle the high speeds.

That brings us to eBay. EBay is notorious for selling counterfeit HDMI cables and sometimes at prices higher than you can get at reputable places like Monoprice and Blue Jeans Cable, etc. That all three of your cables came from eBay makes me suspicious about the cables' pedigree.

That an audio dropout and video dropout *can* be a sign of bit errors also makes me suspicious. One (not conclusive) test you can run is to drop the Radeon's HDMI output to 1080i (I'm assuming you are at 1080p right now) and see if that clears your problem. By doing that you are dropping your output bandwidth in half (roughly). Also make sure Deep Color is disabled on all devices and that you have resolution set to "pass through" (or words like that) on the AVR.

Yes, this can also be a sign of a handshake issue between your AVR and the Radeon. However, in that case I would expect you to not regain your video and audio again without a power cycle. The only thing you can do in the case of a handshake issue is to see if your firmware is at the latest level - first with the AVR and then with the Radeon. A handshake issue is pretty much unfixable except for trying different HDMI options (such as disabling CEC) and checking the firmware.

Finally be very cautious of cable manufacturers that advertise an HDMI revision number on a cable. The HDMI Org (which owns HDMI's patents and trademarks and first borns) back in November 2010 mandated that *no* version number be included in advertising. Just "high speed" or "standard speed" to make it easier to choose an HDMI cable.

http://www.hdmi.org/consumer/buying_guide.aspx

That you found a cable that is violating this HDMI rule means it is probably either counterfeit or old - although using 1.4a makes it seem relatively new.

You seem to have eliminated the computer as a source of the problems. Bad drivers could also cause these symptoms but that it works connected directly to the LG makes me think it isn't there. However, since the LG is stereo and your AVR would be multichannel, I'd bet different drivers are in use (or at least used differently) when connected to the AVR, assuming you are doing multichannel work. Does the same problem occur if you are using a stereo source?

If both the flat panel and the receiver support ARC, then you can. However most HDTVs do not know about DTS-HD so I can't imagine that would work unless the HDTV specifically said it supported it, no matter how you manually change the EDID.

Do the LG and Onkyo both support ARC?

Also make sure any cables you use are labeled as HDMI High Speed and that they are formally certified for high speed (not just independently tested). There are only two types of HDMI cables with some options - High Speed and Standard Speed.

With HDMI cables more money isn't better. You'll find an append on that subject in today's appends (see Monster cables). If the cable was reviewed by WhatHiFi, then you can throw out that review - no data, just words.

Really the only thing that counts is a certificate, other users' comments and your own experience.

Not sure how to convert back to pounds but I would expect a good high speed 2 meter cable to be about $6 from a reputable online vendor.

The cable I've purchased won a few awards in 2010 - the category being 'most heavily advertised in our magazine'

You potentially have two unrelated problems!

ARC has proven to be problematic for some kit combinations - ensure you have the latest firmware running on your TV and AVR!

The drop out when you have PC> AVR -> TV may require an EDID grabber between the PC and the AVR.

Whilst ARC can carry multi channel audio there is a high probability that you are limited to video + 2 channel audio going into your TV via HDMI.

Joe