Syntax issue with converting over from wavwrite to audiowrite

[RT]

In Octave 3.8.1 I'm able to export a stereo wave file using the command below
wavwrite([w1(:) w2(:)],44100,16,'/tmp/testfile.wav');

I'm trying to get it to work with audiowrite using octave 4.0 see below but I get a audiowrite: wrong argument name

audiowrite('/tmp/testfile2.wav',[w1(:) w2(:) w3(:) w4(:)],44100,16)

and
audiowrite('/tmp/testfile2.flac',[w1(:) w2(:) w3(:) w4(:)],44100,16)

It says audiowrite can have up to 256 channels am I incorrect about this?

Thanks