| Symptom | Likely Cause | Fix | | :--- | :--- | :--- | | Hot at idle | Bad EEPROM/Standby mode disabled | Return for refund | | Hot only with low-ohm IEMs | Amp current overload | Use 75-ohm adapter | | Hot on PC but not on phone | USB port supplying >5.2V | Use a powered USB hub | | Case is hot, but chip is fine | Poor thermal conductivity between chip and case | Open case + thermal pad | | Intermittent cutting out | Thermal shutdown | Undervolt via software limiter | The CX31993 is incredible if you manage its thermal envelope. For reference, its competitor—the ALC5686—runs 10°C cooler but has worse THD+N.
By applying the , performing the Thermal Pad Mod , or simply buying an impedance adapter, you can continue enjoying 384kHz playback without burning your fingertips. cx31993 datasheet fix hot
However, a widespread issue has plagued users across Reddit, Head-Fi, and GitHub forums: | Symptom | Likely Cause | Fix |
But when you plug in headphones (32 Ohm or lower), or use a passive analog volume control (like a USB knob), the amplifier enters a Class A/B bias region where efficiency plummets. However, a widespread issue has plagued users across
A thermal pad (1mm thick) or Arctic Silver thermal paste, and a small aluminum heatsink (e.g., Raspberry Pi heatsink).
So, why is your dongle hitting 45°C (113°F)?
The answer lies in the . The CX31993 contains an integrated headphone amplifier . The datasheet specifies that the chip can drive loads down to 16 Ohms. When you plug in high-sensitivity IEMs (like the Moondrop Chu or 7Hz Zero), the amp section works fine.