Roku disconnecting

I have not attempted any port forwarding for the Roku.  This website talks about opening ports for the Roku:

https://forums.roku.com/viewtopic.php?t=20399

However, I usually thought that port forwarding was necessary when I was not getting any connection to the internet at all.  In this case, my Roku connection to the internet is fine.  The problem is that my phone (which is connected to the same network) will all of a sudden stop "discovering" the Roku player, and then the Roku app on the phone stops working momentarily.  I have to attempt "retrying" the connection a few times until it comes back.  This happens periodically throughout the course of watching a movie.  However, the movie never stops playing and the Roku seems to be connected to the internet just fine.  The only thing I could think of was that the Roku was buffering/losing connection for a split second, and that was enough for the phone to break its connection from the Roku entirely.  However, the wifi signal strength shows "excellent" for the Roku and I cannot confirm this is the case.  

With my scenario, do you think that opening ports will help? In other words, does opening ports help in scenarios where the connection spotty, or is opening ports only applicable when there is no internet connection at all?  I've set the Roku IP address to static and that didn't seem to help.