I have set up a MOCA network with my Tivo Bolt and three Tivo mini's using a HD antenna. My streaming speeds are really slow on the network and I can barely stream Netflix or Youtube on the Mini's without dropping or hangup issues despite having high speed service. I did a speed test right off my modem to a laptop and on the Comcast site it said I was getting 70 Mbps speeds, but when I used the Google speed test speeds are 7 Mbps. On Wifi I am getting 8 - 10 Mbps speeds. Is this a networking issue, a Moca issue, do I need to add ethernet to coax adapters? Enclosed is a picture of my network setup:
First, I'd suspect your antenna. Disconnect it and see what you get. Also, can you post your modem signal levels, please? A screenshot is ideal.