DJI Mic Watcher

DJI Mic Mini TX units enumerate as generic USB mass storage devices on Windows, defeating VID/PID identification. This watcher polls for removable drives and applies a two-stage matcher: first checks disk model/PNP device ID against regex patterns to flag potential DJI mics; then fingerprints the device by scanning for TX##_ filename prefixes in recordings, which are firmware-baked and invariant across machines, ports, and reformats.

The project emerged from a hard constraint: identical DJI Mic Mini units share the same USB serial, volume serial, and disk size, so Windows MountManager binds the Volume GUID to the *drive letter* rather than the physical device. Live testing revealed that swapping which mic goes into which USB port would flip the GUID binding—making Volume GUID unusable as a primary identifier. The solution: privilege the filename prefix (the only firmware-bound signal) and use GUID hints only as a fallback for brand-new uninitialized mics.

The tool runs as a Node.js daemon with zero runtime dependencies, shelling out to PowerShell for drive enumeration (avoiding native module build chains). It tracks state.json to detect and log recording additions/removals each time a mic is attached, paired with human-readable owner labels (Myles, Kaitlyn/Guest) for each TX unit.