Batch downmix AAC 5.1 to AAC 2.0

Hi guys! I have this AAC audio file, and i want to downmix to 2.0 AAC.. how can i do in batch mode? This is the Mediainfo report, i don't undertand why i have 2/6/6 channel!!! ?!?! Code:

Well this is going to be informative thread since I've never seen anything like that mediainfo before. What does it show when you throw it in Audacity?

Yep, is not a normal AAC. Seems a mix of different AAC streams. The HE-AACv2 can't have 6 channels, is a mono channel with extra info (Parametric Stereo) to obtain 2.0 I don't know if there are a decoder than can preserve the 2.0 parts and downmix the 5.1 parts on the fly. The decoders must be initialized each time than change some important parameter, like the channel number.

ffmpeg should be capable to do this things - from some time decoder is able to follow changes in stream (common in satellite). I would try something like this: Code:

Perhaps this is LFE and LFE content is empty? Happen sometimes...