The channel layout must start with 0x, otherwise it is parsed as a
number of channels.
will instruct the source to accept planar 16bit signed stereo at 44100Hz.
Since the sample format with name "s16" corresponds to the number
-1 and the "stereo" channel layout corresponds to the value 3, this is
+1 and the "stereo" channel layout corresponds to the value 0x3, this is
equivalent to:
@example
-abuffer=44100:1:3:1
+abuffer=44100:1:0x3:1
@end example
@section aevalsrc