@bod
No signal is a message from the TV, not the Roku, indicating the TV is not receiving a signal via the selected input.
You've tried multiple TVs.
You've changed cables.
The model 3930 was released less than three years ago (September 2019) meaning you should still be getting good service from it. At least, I think you should.
If you've had it four years, you might want to verify the model number. Since you're getting no signal, you'll need to find it on the device itself.
The only thing to do different would be to put it in place of another HDMI-connected device. For example, if you have a game system, Blu-Ray player, or any other HDMI-connected device, then power down, take the HDMI cable from the other system, connect it to Roku, then power up. That rules out a bad cable replaced with a bad in the box cable.
Apart from that, I'm out of suggestions.
DBDukes
Roku Community Streaming Expert
Note: I am not a Roku employee.
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