audio: Fix resampler overflowing input buffer.
This usually manifests as a clicking sound, because it often produces
a value outside the range -1.0f to 1.0f based on whatever random data
is past the buffer, which later stages of audio conversion will clamp
to a maximum value for the audio format. Since this tends to be a single
bad sample generated at the end of the resampled buffer, it sounds like
a repeating click in streamed data.
I'd like a more efficient means to clamp this value to not overflow the
buffer, but this puts out the immediate fire.