Can I use the $19.99 remote that has tv volume control with my 3900X?
Yes, its the 3700 express that can't be paired to a wifi remote, wifi remotes are the only roku remotes with tv controls. Other then true Roku tv remotes. So your roku 3900 will work, once paired.
Yes, its the 3700 express that can't be paired to a wifi remote, wifi remotes are the only roku remotes with tv controls. Other then true Roku tv remotes. So your roku 3900 will work, once paired.