There seems to be an issue with this at the moment, I'll take a look.
I might have mentioned this on another thread, but I rarely ever found the need to process audio clips in this way. I usually just load the audio directly into Csound using a table, or the diskin2. For example, the following instrument will load a file called pianoSample.wav from the Assets/Audio folder and start playing it back.
form caption("Test"), size(300, 200)
-n -d -m0d
sr = 44100
ksmps = 32
nchnls = 2
0dbfs = 1
SPath chnget "AudioPath"
SFilename sprintf "%s/pianoSample.wav", SPath
a1, a2 diskin2 SFilename, 1, 0, 1
outs a1, a2
i1 0 [3600*12]
I'll need to fix the issue with 'Process Clip' before you can access mic input.