I'm getting Playback conversion errors- Files won't play

Some movies won’t play at times, it tells me “Failed Playback conversion errors” This just started to day on files that I’ve used previously so I know it’s not the file that has a problem so I’m thinking it must be the server that has an error. Can anyone help?

I am using the newest server updater and the problem is playback on my Roku is stopping do to “Conversion Failed” or “Transcoder Failed” according to the message I get. This happens several times per episode sometimes. I have Version 1.11.0.4666. and my upload and download speed should be fine @ 112 MB down & 12 MB up. Is there anything I can do to stop this?