Here's how many HDMI cable manufacturers “test” their products: They run a cable between a display and a Blu-ray player all day long, and if the video transmits, the cable is “good.”
While such a test might reveal that a cable can pass video, it doesn't do anything to show interoperability among HDMI-connected devices, especially when tolerances are so tight, as with Rev 2.0 and 18G performance guarantees.
So how can you test for interoperability? One factory DPL Labs visited overseas tests cables between 10 displays, 10 sources, and four generators. If a product works with more than five set-ups, it moves to production.
But what kind of test standard is that? Is it always predominantly these five set-ups or does this matrix change with different source products?
It doesn't make sense.
What happens when manufacturers change their products? A bigger screen. Support for HDR. An extra input. Diagnostic software. A 'little' firmware update….
Every little change brings new interoperability issues.
Back to the factory that so diligently tests cables on multiple source/sink set-ups. What good will those tests be in six to 12 months? Most likely a good chunk of the testing gear will be replaced with other products. Does this mean they'll re-test the cables? Not going to happen.
What's the answer? Continue to test cables in the lab, of course, but one of the surest ways to make them work in the field is to learn from each other.
All the lab testing in the world won't catch the interop issues that dealers discover in the field. Keep that data coming in!