Hi RAK team, I am currently working on a project using the following setup: RAK11200 (ESP32), WisBlock base (USB powered), and RAK18061 audio amplifier module. The system was initially working correctly with standalone audio playback (WAV playback using I2S and TAS2560), and audio could be triggered without any issue. Later, I extended the application to include WiFi connection, MQTT subscription, and audio playback triggered by MQTT messages. During testing, when triggering audio while WiFi was active, the system entered a reboot loop (USB connect/disconnect continuously), and the board kept restarting repeatedly. After this event, the RAK18061 module stopped working.
Currently, with this specific RAK18061, AMP.begin() always fails, and an I2C scan does not detect any device at address 0x4C. The module does not respond at all on the I2C bus. I performed several cross-checks to isolate the issue: replacing the RAK18061 with another unit makes the system work correctly, the same firmware works fine with the new module, and I also tested minimal firmware (no WiFi, no MQTT, no audio loop). I tested with and without speaker connected and performed a full power cycle (USB disconnected, module removed, waited several minutes, and reassembled the system). The result is that the problematic module is still not detected on I2C.
Based on these tests, it appears that this specific RAK18061 is no longer responding on I2C and may have been affected during the reboot or brownout situation. I would appreciate your guidance on the following points: Is there any way to reset or recover a RAK18061 (TAS2560) once it stops responding? Can the module enter a latched fault or protection state after brownout, overcurrent, or unstable power conditions? Is it expected that the module may become permanently non-responsive in such scenarios? Are there specific power supply requirements or recommendations when combining RAK11200 (WiFi active) with RAK18061 (audio playback)? Should WB_IO2 be used to control the amplifier power, or is it recommended to keep the module continuously powered?
Additional context: the system is powered only via USB, and audio functionality was stable before integrating WiFi and MQTT. The issue appeared only after combining WiFi, MQTT, and audio.
Any guidance or best practices would be highly appreciated. Thank you very much for your support.
Best regards,
Younes