moca network and problem with samsung set top box

I currently have both a TiVo Roamio Pro and a Samsung set top box from Optimum/Cablevision so I can use on demand and previously recorded shows. I set this up by connecting them to different inputs on the TV. From the wall coax, I have a splitter, so each device gets a cable line. This worked well while the TiVo was on WiFi. However, I recently purchased a MoCa adapter which I set up by my cable modem as per the TiVo instructions. When I enable MoCa on the TiVo it gets a connection, so I believe the MoCa network is functioning. However, if MoCa is enabled the Samsung set top box won't work. It will just say "7:00" which my research shows means it doesn't have a cable connection. I did get it to boot up finally, but it still intermittently flashes CuC indicating a connection problem, and now won't boot at all. Once I disable MoCa and switch the TiVo back to WiFi the Samsung box works again. Another Samsung box in another room (off of different cable outlet) has not had a problem.

Could my problem be with the splitter in the room that has 2 boxes? Could the Samsung box not work if there is a MoCa network? Short of wiring ethernet cables all over the house, what are my options, as I'd like to install some TiVo Mini's so I can not use WiFi. Would a filter on the line into the Samsung box do anything?



Thanks.