Remotely Connecting from 2 Networks

I recently made some big changes to my network as I was having a lot of challenges with my prior network. I now have 2 seperate networks.

Network 1 (192.168.2.XXX):
2 access points (sharing a common SSID) connected to my ISP modem where everything in my house is connected to them other than my audio related stuff.

Network 2 (192.168.1.XXX):
A router which is coonected by its WAN port to the LAN of the ISP Modem where everything audio related is connected. I have 2 Roon Ready devices and a NUC running ROCK. I use an Android phone to connect remotely.

Let me say that this has solved all of my prior issues with drop outs, disconnections and Roon connectivity. However, I have one outstanding issue I can’t solve:

When connected remotely to Network 2, everything functions great as it should.

When connected remotely to Network 1, sometimes it will connect to Roon (which is on Network 2) and other times not. It always connects when on Network 2.

Any suggestions as to why this may be? If it never connected via Network 1, I would chalk it up to that is the way the networks are now configured. The fact that it sometimes responds from the other network and not at other times is what has me confused.

Roon requires everything to be on the same subnet.

Understood. That is why I’m wondering why it sometimes works from the 2nd network.