I have a 55" TCL Roku tv and a Samsung soundbar. The sound bar is connected to the ARC HDMI plug with an HDMI cable. For some reason when I turn on the tv the sound bar doesn't turn on. Is there a special HDMI cable required? Any thoughts on this issue? If I turn the sound bar on manually via the remote that came with it, it works fine.

I believe you have to turn on CEC in the TV's settings for this to work. There is a section in the system settings to activate this.

As @scottypie1234 mentioned, you'll want to enable HDMI CEC settings on your TV, which should enable this functionality for you. 

Visit Settings>System>Control other devices(CEC)>and try enabling 'ARC', and 'System audio control'. 

Let us know if that helps get things on track! 


Cheers,
Tanner