With default sink set to a different-endian machine:
$ gst-launch-0.10 audiotestsrc ! audioconvert ! audio/x-raw-float ! pulsesink
Setting pipeline to PAUSED ...
Pipeline is PREROLLING ...
ERROR: from element /pipeline0/pulsesink0: Failed to connect stream: Invalid argument
Additional debug info:
pulsesink.c(399): gst_pulsesink_prepare (): /pipeline0/pulsesink0
ERROR: pipeline doesn't want to preroll.
Setting pipeline to NULL ...
FREEING pipeline ...
Meanwhile the other end has
sink-input.c: Unsupported resampling operation.
This is because sconv.c pa_get_convert_{to,from}_float32ne_function does not handle PA_SAMPLE_FLOAT32{B,L}E. Converting to an int format works fine.