Replying to all three comments, thanks for the interest.
In no particular order,
Equipment
I have a PC, 12th Gen i7, 23 cores. 20 threads, 32GB of RAM, plenty of horsepower. I used to run JRiver on far less.
My amp is an Anthem STR integrated amplifier. Modern digital processing. You can look up the specs, it has no trouble handing USB input.
The source music is naturally not all at the same bitrate/depth, but the point is that I have JR resample it all to the same 96 kHz, so if JRiver is doing what it says, the amp is not seeing any change in sample rate, ever. It should all leave the computer at 96kHz.
I use a USB connection because the HDMI output I use for video to my TV/monitor. I don't want to root the sound through the TV on the way to the amp. I like to be able to leave music playing and turn off the TV entirely.
Regarding the skip/dropouts, these are considerable less frequent since I've upped the buffering, but they still happen occasionally when I just sitting and listening to music. Presumably the computer is doing something n the background an JRiver goes AWOL for a bit, but that never used to happen before I went to the USB transfer.
While the occasional skip is annoying, usually the music jumps forward a second or so - not a problem with file because if a go back and play it again, it doesn't happen. But the tick/pop that happens when I skip forward from the middle of a track to the next song or start a song, sometimes even when nothing has been playing is very, very annoying. Particularly at higher volumes.
Someone would have to work pretty hard to convince me that the noises that happen between tracks as described above aren't the failure of the program that is supposed to be delivering a seamless 96 kHz stream to the amp, but I'm open to been showing how to make it go away.
Thanks for your time.