I only use a local audio device, that is I have a USB audio adapter, because the PI does not have microphone support.
The problem I have in my software is that the decimation factor is not constant, The radioberry is not running exactly 384 Khz and
the Raspi audio card is not exactly 48 Khz. This will result in buffer over- or underruns. What I saw in the code of pihpsdr that it drops data when the decimation is not aligned.
PC software is maybe more advanced. I now measure the buffersize and adjust the decimation accordingly. For me this is good enough, but a more advanced feedback loop would be better.
You also do not want the buffer to grow too large that is causing unwanted delays.