I have the A-200. For 2 years I had no issues at all, until one day started to stutter. I troubleshooted my server and network for hours and nothing. Then I checked the popcorn, nothing.
At one point I changed the video output option from 1080p24 to 1080p60... problem fixed. Finally I changed back to 1080p24, not a single issue.
Who knows, it may be an unknown bug. You may try this fix.
EDIT: Try using the 100Mb connection, save changes, this is more than enough to stream blu-ray isos