Ah, it's possible analog31 isn't using ASIO card, I assumed they are as they seem to have tried to jam before so also assumed they were a musician and I haven't met many who doesn't use ASIO in the first place.
Ah, that's interesting. I'm using a USB audio interface. It claims to be ASIO compatible. Oddly enough I tried the same interface in different computers, and have tried other computers, but haven't dug much further than that. I've also tried all of this on a decent Ubuntu box, and I've now got it running on a Raspberry Pi 3 since the overall latency has been more less the same in all cases.
We're all analog musicians playing alcohol powered instruments. ;-) Some of us are techies, others not. While I'm a techie, that side of my life has always been somewhat separate from the musical side, so I haven't paid that much attention to the digital technology until the pandemic came along. But I'm happy to learn, especially if something simple can make it work better.
I think WASAPI has comparable latency to ASIO drivers. I can get around 20-30ms latency with WASAPI though ASIO takes me down to 10-15. Granted I'm using a dedicated USB audio interface though.
You should be able to easily sustain below 5ms buffer size, and RT_PREEMPT Linux has no problems keeping a few hundred microseconds of buffer filled (a suitable PCIe soundcard should easily make 100us buffer level reliable; that's 9.6 samples at 96kHz sample rate).
Yes, sub-ms latency is hard. But the infrastructure exists.