Anyone experience frame stuttering/video dropouts during particular shows?

Ran two Roamios with a splitter which appears to work well for most shows on NBC, but in recording the "Blacklist" last week on Comcast, there appeared to be a constant frame drop causing a periodic freezing every few seconds all during the show...incredibly annoying. Most other shows on NBC were fine. Have the latest firmware revision on both and the line from the junction box to my apartment unit has been new for the last month. In the prior revision of firmware, I'd have the typical audio dropouts and minor video glitches, but this was really bad. Strange, it was only during one particular show. Waiting to see if it happens this week again.

Also, had my Premier on a separate feed recording the show OTA and it was perfectly fine.