Hi I am developing a phone app using pulseaudio 6.0 with asynchronous API using Bluetooth Headset. I create a record stream with pa_stream_new() with this parameter. static pa_sample_spec samplespec = { .format = PA_SAMPLE_S16LE, /* Linear 16bit */ .rate = 16000, /* 16000Hz */ .channels = 1 /* mono */ } And I set a callback function by pa_stream_set_read_callback(). After the stream created, I could get a voice data by 96byte per 10ms in this callback.I checked a log with clock_gettime() in this callback. I think I get voice packet by 320Byte per 10ms. 16000Hz * 1 * 16bit = 256kbps = 32KBps This means that I can get 320Byte per 10ms. So I need to get 320Byte per 10ms. I set sample format above, but I got different voice packet from callback. I would like to get a voice with Linear 16bit 16kHz mono. Is there additional configuration to this codec? For confirmation, when I use a bluetooth headset, Is this correct the pulseaudio convert codec from SBC to Linear as follows? My app <- Linear 16bit 16kHz <- Pulseaudio <- SBC codec <- Bluetooth Headset And addition to that, After stream connected, CPU load for pulseaudio rose up 50%-60%.CPU load for MyAPP rose up 20%-30%. In order to reduce CPU load, I conigure as follows: high-priority = no realtime-scheduling = no resample-method=trivial Best Regards, Shinnosuke Suzuki -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://lists.freedesktop.org/archives/pulseaudio-discuss/attachments/20180208/f5f67e27/attachment.html>