[doveman2]

Try plugging the RPi into another HDMI port on the TV. CEC might only work on port 1. If you are plugging into an AV receiver then that will go in HDMI 1 on the TV and the RPi should go into HDMI 1 on the AV receiver. I looked up this unit and I didn't see any mention of CEC capability but most manufactures don't mention it anymore or re-brand it. A call to the vendor of the TV might confirm that CEC is available.

I tried both HDMI ports and the menu has a CEC On/Off setting and OE said CEC device detected, so it does have some sort of CEC but it must be some weird version that doesn't work with the Pi. Apparently it's not very standardized, even amongst sets from the same manufacturer.