The sound playback component drops data when it receives data faster than it can play it back.
This behavior was originally chosen for a waveform where the input data sample rate was set by the USRP and the output rate by the sound car. Since an overrun in this case is a problem, I decided to drop data on overruns.
Now I have a waveform that reads data from a file, processes the data, and sends it to the sound card. Obviously, this leads to drop data and now flow control back to the FileInput? block. I plan to change the sound playback routines to block, rather than drop data. We should watch to see if this is a problem for waveforms that receive data from fixed rate sources.
