This unit was posted over on a Goldwing Facebook page as a reliable solution. Supposedly the same unit as a JL Audio unit. YMMV.
https://scontent-atl3-1.xx.fbcdn.net...85&oe=5C377C19
https://scontent-atl3-1.xx.fbcdn.net...7d&oe=5C1DBB64
https://www.sonicelectronix.com/item...er-MBT-RX.html