Recorded OTA Video Stuttering but Audio Continues or Not Synced

Good news it only happens on one sub channel. Not all shows do this. Some play back normally.

Station is 5 miles with good shot, using attic 8 bay bowtie antenna
Hard Drive is a new Toshiba 2TB, WiFi Router Asus RT-AT66U 5G
Tablo 4th Gen is connected to router via Ethernet.
Roku 4K streaming stick (Roku Express tried first did not work well).

This issue seems to be only on this channel, sub channel 50.4 of ION-SD standard definition. I record mostly ABC, CBS, NBC, FOX, PBS, typically on X.1 or XX.1 primary channel. I record PBS on 10.2. Seems OK.

**OTHER CLUE and WEIRD ISSUE… Clicking on show ICON for the show I recorded on ION DEFY, it does NOTHING… pull out phone and used Tablo phone App. Screen is black for a few seconds and show starts… Theen when I go to TV / Roku the show loads? I also cycle power on Tablo.

I have a lot of guesses but want your opinion. I have another DVR that I will try to see if I am getting same issue. Like I said DEFY on 50.4 is a new network on ION. They may have data transmission or encoding problems?