GTM-21 FM Traffic Receiver

 

My nuvi 775T came with a GTM-21 traffic receiver.
I have always received FM TMC traffic in the Toronto, Ontario area on my 775T.
Recently it stopped to show traffic information and the little traffic icon on the map screen.
Clicking: Tools > Setting > Traffic > it shows Navteg (US, CAN) Lifetime Subscription.
The status LED on the GTM-21 is solid yellow, indicating that it is searching for signal.
I moved the cable and the antenna wire to different locations around the dashboard and also did master reset on the 775T, still no traffic info.
My newer nuvi models (3790 and 3597) still show traffic in the Toronto area, so there is traffic signal available.
The nuvi 775T is working perfectly otherwise.
Any advise would be greatly appreciated to help me restore the Lifetime Traffic Subscription on my 775T.

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Garmin 660, 775, 3790, 3597 and ecoRoute HD.