USB connection and permissions
Identify adapters, power problems and receiver contention.
Use a cable that carries data, not a charge-only cable. The phone must support USB Host/OTG. A receiver draws power; some phones need a powered hub or a different adapter.
Approve the system USB permission prompt only for the connected receiver you intend to use. If you cancel, reception stays unavailable until you grant access. Unplugging invalidates the current receiver connection.
Only one application can claim the receiver interface at a time. If another app or browser tab holds it, stop and close that receiver session before reconnecting here.
The browser edition uses WebUSB when supported. A Windows browser may also require an appropriate USB driver; that is separate from Android’s native USB Host permission. The hardware guide explains the platform differences.