no HDV 4 audio chanels capture possible ?

Hi,

This is the problem: my sony 270 HDV shoulder camcorder can record four independant audio channels, but it is impossible to capture more than 2 channels (left/right)  in premiere pro (CS6), and no possibility to select channel 3 and 4 in the audio preferences... No result neither with the 5.1 option...

I could do the job with my old Avid Liquid