FAQ & Troubleshooting

The jaw servo only responds to triggered voice tracks and line-in audio. Ambient background audio (from the /ambient/ folder) does not drive the jaw. This is by design — background audio is meant to be atmospheric, not speech.

Line-in audio passthrough only works when Background Audio (BG Audio) is set to OFF in the menu. When BG Audio is ON, the board plays WAV files from the /ambient/ folder instead. Turn off BG Audio to hear your line-in source.

The audio input is line-level only. Passive electret microphones (most cheap 3.5mm mics) produce no sound because the board doesn't provide bias voltage. You need either a self-powered USB microphone, a dynamic microphone, or an inline battery-powered preamp like this one. With a preamp, you can use any standard mic for live puppeteering.

Cheap USB hubs and computer USB ports can inject audible noise into the audio output. Use a quality phone charger or dedicated 5V supply for clean audio. The 12-24V barrel jack input is preferred for final installations — it provides the cleanest power.

The encoder adjusts different volumes depending on what's playing. During trigger playback it adjusts Voice Vol (triggered WAV tracks). At all other times it adjusts BG Vol (ambient audio + line-in passthrough). A popup overlay shows which volume is being changed.

WAV files must be 16-bit PCM format. Other formats (24-bit, compressed, MP3) are not supported. We recommend 44100 Hz, stereo for best results.

The MicroSD card must be formatted as FAT32. exFAT and NTFS are not supported. Cards over 32GB may need to be manually formatted as FAT32 using a tool like SD Card Formatter.

File organization matters:

/audio/ — Triggered voice WAV files
/ambient/ — Background ambient loop WAV files
/eyes/ — Custom eye packages (.eye files)

The board scans these folders at boot and sorts files alphabetically.

Custom eye files (.eye) go in the /eyes/ folder on your MicroSD card. They are scanned on boot and appear in the eye style menu alongside the built-in eyes. Switching is instant. Create custom eyes with the free Eye Creator Tool.

Trigger input is intentionally ignored while you're in the menu or the audio browser. Exit the menu (long-press the encoder, or select Save & Exit) to return to normal operation.

After a triggered audio track finishes playing, the cooldown timer prevents re-triggering. The default is 30 seconds. You can reduce this in the menu under Delay — it goes as low as 5 seconds. The cooldown starts when the audio finishes, not when the trigger fires.

This depends on how the displays are mounted in your skull. Go to Menu > Eyes and use Flip L, Flip R, or Swap to correct the orientation without rewiring. Changes preview live as you toggle them.

On first boot, the jaw servo is intentionally disabled to prevent unexpected movement. You need to enter Menu > Jaw, set the open and close positions, then save. Once you've set and saved jaw limits, the servo will respond to audio.

Two ways to save:

Long-press the encoder from anywhere in the menu to instantly save and exit.
Scroll to [Save & Exit] at the bottom of the main menu and press.

The menu also auto-saves after 60 seconds of inactivity. If you want to discard changes, power cycle the board before saving.