I am having the same problem with the Acorn Channel and a Roku Streambar Pro (9101R2), I noticed this problem occurring after updating to 11.5. Acorn is working fine with Roku Ultra's and Streaming Sticks I own. I worked with Roku Support the past 2 weeks and performed all the steps they suggested:
- Check for new Roku OS Updates, Check the Acorn App Version, Delete Acorn App and Add Back.
- Reset Roku OS to Factory Settings (which is a pain because I had reset all of my Roku Speakers, check for new Roku OS, Delete Acorn App and Add Back
- Provided them with a video recording of the problem, which they never acknowledged receiving.
- Last Support Rep I chatted with finally gave up and told me to contact Acorn since that was the only channel I was having trouble with. I asked him several times if they received my video recording of the problem and he wouldn't respond and then he cancelled the Chat because I brought up another problem I was starting to have with Remote not controlling On/Off with Samsung TV.
Needless to say Roku Suppport gave up on problem and Now I am working with Acorn Support to resolve issue. Roku Technical Support is only helpful up to a point and You are battling with 2 vendors.