I apologize that I am not quite the right person to be posting this problem on the forum, since I am a customer rather than the developer of the channel in question, but I have tried submitting a bug request through Roku (#4437802, #4451686, and #4437802) and get the distinct idea that my reports got binned rather than forwarded to the dev team (lets just say I was not impressed). But if this avenue gets to the right place that is better for all involved.
The problem is that on a specific private channel, I-ON TV (code: ion, https://www.i-on.tv/) all of the video is black on my RokuTV (Sharp LC-43LB371U). The control interface comes up and I can switch streams, and I even get audio, but the video is always black. To work around that issue I have also purchased a Roku HDMI streaming stick (3500R), which shows the same video successfully when plugged into that same RokuTV. Since I bought a RokuTV in part to get down to just one remote this galls me a bit.
I wound up talking to the CEO of I-ON TV/eMedia Network, and he seemed to indicate that at times they were able to get it working on RokuTV models in their labs, but that almost always the next update from Roku would break it again. Regardless of what the issue is, they don't seem to have a handle on what makes RokuTV different from other models. My goal is to have someone from the Roku development team reach out to them to help sort out the issues they are having. Presumably if they are having this problem, someone else is going to run into it as well.
That might be it, since they start out with a "channels" (as in TV channels) list overlaid on top of the the playing "channel", which then drops down. Without learning the API myself, that sounds like a good possibility. Is there a workaround for this problem, or is a fix coming in a future version of the OS? And any chance I could have you get in contact with I-ON TV/eMedia Network to help then fix the problem?