Internal DAC audio broke in v4.4 (IDFGH-6715)

[cfint]

Environment

• Development Kit: none
• Kit version: none
• Module or chip used: ESP32-WROOM-32
• IDF: v5.0-dev-1446-ga470ae224d
• Build System: idf.py
• Compiler version: xtensa-esp32-elf-gcc (crosstool-NG esp-2021r2) 8.4.0
• Operating System: Linux
• Using an IDE?: No
• Power Supply: external 5V

Problem Description

I2S internal DAC produces garbled sound with A2DP-Sink example. I've bisected the problem to commit f7f8c9c. The prior commit (2f1247e) does not compile. The most recent working commit on the v4.4 branch is 12c76b4.

The problem still exists on on current master (a470ae2)

Expected Behavior

Analog sound playback through I2S internal DAC.

Actual Behavior

Internal DAC doesn't play correct sound.

Steps to reproduce

1. Install A2DP-Sink example on an ESP32 board.
2. Pair an iPhone bluetooth with the ESP32.
3. Play music on iPhone through Bluetooth audio.
4. Hear garbled audio.

[negativekelvin]

#8327

[cfint]

#8327

That patch works with pschatzmann/ESP32-A2DP. The A2DP-Sink example is kind of working. It has much louder audio and it's full of static.

[L-KAYA]

#8327

That patch works with pschatzmann/ESP32-A2DP. The A2DP-Sink example is kind of working. It has much louder audio and it's full of static.

@cfint That may be caused by the input signed value are output in unsigned value, try the following change to see if it can help:
in examples/bluetooth/bluedroid/classic_bt/a2dp_sink/main/bt_app_av.c line 403, replace the function bt_app_a2d_data_cb with

void bt_app_a2d_data_cb(const uint8_t *data, uint32_t len)
{
    uint8_t *recv_data = malloc(len);
    for (int i = 0; i < len; i++) {
        recv_data[i] = data[i] + 128;
    }
    write_ringbuf(recv_data, len);
    free(recv_data);

    /* log the number every 100 packets */
    if (++s_pkt_cnt % 100 == 0) {
        ESP_LOGI(BT_AV_TAG, "Audio packet count: %u", s_pkt_cnt);
    }
}

[karawin]

Working with patch https://github.com/espressif/esp-idf/pull/8327/files

[dzanis]

This fix broke the I2S ADC, had to revert the old code back