Unstable Internet connection after MoCa

I recently had a MoCa network adapter installed (amazon link) so that I can have a wired connection to a router on another floor. Unfortunately, after setting it up, I have been dealing with a very unstable connection. Multiple times an hour, my devices disconnect from the wifi temporarily and then reconnect. Its becoming very frustrating.  The coax LED on the moca adapter is constantly blinking but im not sure if thats a sign of unstable connection or if its standard for it to blink. 

My current setup is :

incoming coax --> xfinity gateway --> ethernet cable to MocaAdapter --> coax cable from moca adapter to the outlet in another room (one splitter in between) --> outlet to moca adapter -->  ethernet to router. 

Based on other posts in this thread, my assumption is that the problem is either : 

1. using the wrong splitter  
   • based on the label of the splitter the supported frequency is between 5 - 1670MHz so i think this is not the problem
2. PoE filter is not present at the point where the incoming coax enters
   • my understand was that since the xfinity gateway is between the incoming coax and the moca adapter, it would act as a PoE filter. Not sure if thats accurate though.

Can I please get some guidance on how best to proceed with identifying the problem?