i2s_ad_dac example has gaps in playback (IDFGH-7862)

[PilnyTomas]

Environment

• Development Kit: [ESP32-DevKitC]
• Kit version (for WroverKit/PicoKit/DevKitC): [v4]
• Module or chip used: [ESP32-WROOM-32D]
• IDF version: Tried on v4.4.1-581-gee2029c38a and v5.0-dev-4257-g508661b03e
• Build System: [idf.py]
• Compiler version: 8.4.0
• Operating System: [Linux]
• Using an IDE?: [No]
• Power Supply: [USB, directly from computer - no hubs inbetween]

Problem Description

Audio playback is laggy.
There seems to be approx 64.4ms period of playback followed by approx the same length (64.4ms) period of silence - this pattern repeats and the resulting audio is horribly unusable, laggy / chopped.

Expected Behavior

Clear audio without pauses, lags, gaps,...

Actual Behavior

Gaps in playback

Steps to reproduce

1. Setup example https://github.com/espressif/esp-idf/tree/release/v4.4/examples/peripherals/i2s/i2s_adc_dac
2. Listen
3. Record on an oscilloscope

In the pictures, channel 2 is ADC output, and channel 3 is amplifier output

Relates to Arduino-ESP32 issue espressif/arduino-esp32#5938

[PilnyTomas]

Uploading some more pictures - audio file playback - both DAC channels

Overview

Closeup - gap period

Closeup - playback period

[L-KAYA]

The issue can be fixed by changing the I2S configuration from

        .dma_buf_count = 2,
        .dma_buf_len = 1024,

to

        .dma_buf_count = 6,
        .dma_buf_len = 256,

The fix is on the way.

[PilnyTomas]

Hi @L-KAYA, I just tested the example with the new settings and can confirm that the resulting audio is clear and without gaps.