The following from Leo at Elgato.Looks like it may be a while 'til it's useable here.
"My understanding is that within the MPEG-4 H.264 DVB-T signal, there are two audio signals, a low-quality AAC stream, and a higher quality HE-AAC stream. It's not that EyeTV doesn't properly decode the stream, but that its using the lower-quality stream. The format chosen for the higher quality stream is not well supported. To properly decode this stream, we would need to augment EyeTV with an additional codec, which at this point is difficult to acquire."