So Michaels statement that HD 69XX is not supported by this new HDMI patch is simply wrong. This would be right:
All HD 6XXX GPUs have working HDMI sound now! Still waiting for HD 7XXX to catch up.
But I think AMDs internal/external GPU, GPU Familiy, ... names have confused Michael.
But I think I got it (slap me if I'm wrong xD):
Version jump (from 6XXX to 7XXX, for example) means completely reworked GPU core (VLIW -> SIMD).
Family jump (Nothern Island to Southern Island, for example) means reworked extensions (like UVD2 -> UVD3) ... but wait, that doesn't reflect DCE5 -> DCE6 ... so, well, I give up. Only AMD may know the truth about the naming shemes.
P.S. @Zajec according to RadeonFeature HD7450 - HD7670 are NI, too, also HD7350 is a Evergreen...?