Yes, you stop playback in a zone by stopping the file that is playing. You also have to have the correct zone selected under Playing Now.
I have four or five ASIO drivers for various devices (PCIe, USB, Firewire) all installed on my computer. I don't have any conflicts. This doesn't really help you if you are having conflicts
, but I thought I'd mention it. It does make me ask, "How do you know you are having conflicts?"
Do you have either device set as your default audio device? I recommend setting your motherboard output (analog or digital) as the default device. This prevents other software, including the OS, from using the hardware. When they use the hardware, like for internet audio, then that prevents the ASIO driver from accessing the hardware.
What happens when you try to playback to channels 1 & 2 on the Lynx card? Just no sound or do you also get an error message? Have you looked at the Lynx mixer to see if it shows playback on those channels or to make sure the channels didn't get muted or rerouted. I recommend check marking "lock mixer" in the mixer settings after you have verified the settings are correct and no channels are muted or rerouted.
Nothing has to be done in the Lynx Mixer to work properly with JRiver and it really should be left alone. I was "messing around" and inadvertently panned the right channel from far right to the middle. This moved my whole soundstage left and it took me a while to figure out what was going on. I don't mean a few hours. More like several days of looking at every possible thing. After I finally found the problem and fixed it, the settings would revert every time I rebooted. I then had to use "lock mixer" to maintain the correct setting. A re-installation of the Lynx driver/software was actually needed to permanently fix it.