pdprintf("write plugin: %s, %li\n", plugin->name, frames);
if ((frames = plugin->transfer(plugin, src_channels, dst_channels, frames)) < 0)
return frames;
pdprintf("write plugin: %s, %li\n", plugin->name, frames);
if ((frames = plugin->transfer(plugin, src_channels, dst_channels, frames)) < 0)
return frames;