Restore Stock Firmware

Restoring stock firmware uses the standard USB downgrade procedure. The steps below apply to SoundTouch 20/30 models; follow the linked guide for model details and firmware downloads.

1. Format a USB drive of 32 GB or less as FAT32.
2. Download the appropriate stock firmware and copy its Update.stu file, unmodified and by itself, to the USB drive.
3. With the speaker unplugged, insert the USB drive into the rear SETUP B port.
4. Hold preset 4 and Volume Down, then apply power while continuing to hold both buttons. Release them when the update indicator appears, then wait for the update and reboot to finish.
5. Confirm the installed version: hold preset 5 and Volume Down, then use the volume buttons to locate the firmware version screen.
6. Factory-reset the restored firmware by holding preset 1 and Volume Down for 10 seconds.

Do not interrupt power while the update is in progress. For firmware selection, model-specific notes, and setup after the update, see the SoundTouch Firmware Downgrade Guide.