Hardware:
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Device: Radxa Rock 4D
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Firmware: Android 14 (radxa-rock4d-20250528)
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Issue: No audio output from HDMI (headphone jack works)
Problem Description:
After flashing the latest Android 14 firmware, there is no audio output from HDMI. Video output via HDMI works perfectly, and the 3.5mm headphone jack audio works, but HDMI audio does not function at all. The system appears to be permanently routing audio to the headphone jack instead of HDMI.
Root Cause Identified:`
After extensive debugging via ADB, I’ve identified the root cause: **GPIO 148 (gpio4-20) headphone detection pin is stuck reading HIGH, causing the system to believe a headphone is always connected. This forces all audio routing to the headphone jack (AUDIO_DEVICE_OUT_WIRED_HEADPHONE) and prevents HDMI audio from being used.
Request:**
Can the Radxa team please:
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Confirm this is a known issue
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Provide a timeline for a firmware fix
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Release an updated Android 14 image with corrected device tree configuration for the headphone detection GPIO
This appears to be a simple device tree configuration bug that can be fixed by changing the GPIO pull resistor or polarity setting for pin gpio4-20 (pin 148).
Additional Information:
I’m happy to provide any additional logs, test results, or debugging information if needed. I have full ADB access and can run any diagnostic commands requested.
Thank you for your assistance!