nrf5340 Stereo Audio output

Question

Hello, 
 I am using nrf5340 module with external hardware audio codec to test stereo audio output. 
 I use nrf5340 module as the headset to connect with Pixel 7 mobile phone,and refer to this post ,I modify the code to below: 
 static void audio_headset_configure(void)
{
	if (IS_ENABLED(CONFIG_SW_CODEC_LC3)) {
 sw_codec_cfg.sw_codec = SW_CODEC_LC3;
	} else {
 ERR_CHK_MSG(-EINVAL, "No codec selected");
	}

#if (CONFIG_STREAM_BIDIRECTIONAL)
	sw_codec_cfg.encoder.enabled = true;
	sw_codec_cfg.encoder.channel_mode = SW_CODEC_STEREO;

if (IS_ENABLED(CONFIG_SW_CODEC_LC3)) {
 sw_codec_cfg.encoder.bitrate = CONFIG_LC3_BITRATE;
	} else {
 ERR_CHK_MSG(-EINVAL, "No codec selected");
	}
#endif /* (CONFIG_STREAM_BIDIRECTIONAL) */

sw_codec_cfg.decoder.channel_mode = SW_CODEC_STEREO;
	sw_codec_cfg.decoder.enabled = true;
} 
 When playing audio,the noise is very serious. 
 Is there anything else that needs to be modified? 
 The nRF Connect SDK version I used is v2.2.0-rc1.

Amanda Hsieh · Accepted Answer

Hi, LandyWang said: HL [00:00:34.537,078] cis_headset: Frequency: 48000 Hz HL [00:00:34.537,078] cis_headset: Frame Duration: 10000 us HL [00:00:34.537,078] cis_headset: Channel allocation: 0x1 HL [00:00:34.537,109] cis_headset: Octets per frame: 120 (96000 kbps) HL [00:00:34.537,109] cis_headset: Frames per SDU: 1 Seems that it only modified the headset for decoding the received packet in stereo mode. However, the Published Audio Capabilities Service (PACS) is not adjusted for that the headset supports 2 channels. And the default PACS in our project is for TWS topology, which means the headset will only accept one channel audio stream. So mobile phone sends a single-channel encoded frame to the headset, and the headset tries to decode it as stereo audio. LandyWang said: HL [00:00:34.537,078] cis_headset: Channel allocation: 0x1 Mobile phone only sends left-channel data Here is a quick example, (CAUTION: no guarantee and no warranty, just for reference) https://github.com/rick1082/sdk-nrf/commit/70e89352cbc429c29ebe725a7af5ac9a562211d0#diff-42e1fc6ae4cf6357455296de58f9d6343fecd9b4da84da826d9fdf71e5e86eb8 We have to expose that the support channel count is 2 We have to expose that the support channel allocation is left and right -Amanda H

nrf5340 Stereo Audio output

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