Have been using DS Video on Roku successfully for some time. Having added more videos to my Synology server, I can no longer connect using DS Video channel. It seems to make connection to the server and tells me "Retrieving....", but after about 10 seconds it gives an error message "Failed to connect to the DiskStation. Please check the connection or IP address." If I click OK, it goes back to the Settings menu.
I submitted a Trouble Ticket to Synology and they responded saying that the connection to the server simply timed out, suggesting that Roku simply timed out by not giving the DS Video app enough time to complete what it was trying to do. BTW, DS Video works fine using Windows 10 or on Apple devices (iPad, iPhone me , etc.) Here is Synology's reply to me:
The fact Quickconnect is working when you employ it with DS Video on other devices would suggest that the service is working properly, and the fact it's failing to connect on the Roku is probably as I mentioned before - it can probably connect but is timing out due to taking too long. Why this is happening isn't as clear, but is likely because the Roku may have a shorter window to connect before it considers the delay too long. Whether this can be changed or not is another matter: as mentioned previously, support for the Roku version of DS Video ended in 2018, and so there really isn't anything that would be changed or modified on the Synology application; and whether Roku would be willing to make adjustments to the firmware of their device to accommodate this is something only they can answer.
I am hoping that this is something you can help with -- extending the timeout threshold for the DS Video app.
Thank you for all you can do. My family would much appreciate being able to view their videos via the reliable and easy to use Roku way.