HW-Ms650 TV ARC problem

[Gatering]

Hi guys, i'm an owner of a soundbar Hw-Ms650.

2 days ago, i've upgraded the firmware to the lastest version (i've not done any upgrade since i bought it).

Now, when i start my bluray player, Lg UBK90, the bar is switching from HDMI source to TV ARC and then, after 2 seconds, to D.IN.
My display, an optoma UHD60 projector, does not recognize anymore the source.

There's a way to downgrade the firmware to the factory setting?

Tnx

[Gatering]

searching on various forum, i found that the solution is to disable the HDMI CEC feature.

Since is not present the option on both the device, i've taken an old HDMI cable and manually remove the 13th pin, that control the CEC.


now is working surprisingly well ..