==== UPDATE ====
Hopefully this will help anyone else going for this interface.
I noticed that there are certain combinations in the Audio Control Panel that do not work. You do actually get a warning, but I hadn't noticed it. I was wondering why my SONAR sounded horrible, and slow - like it was at the wrong sample rate! In fairness - it *does* warn you... (I wasted a lot of time with this)
I moved the USB connector to a USB port on the mobo, and it's not sharing a "Generic USB Hub" with anything else.
It did seem pretty much the same on a USB3 port on the mobo too.
==== Audio Control Panel settings ====
I've set "USB Streaming Mode" (the hidden buffers) to the lowest setting - and then adjust the ASIO Buffer Size.
- 64 samples (4.9ms RT latency) - Works OK without crackles but only with very few audio and/or soft synth tracks.
- 128 samples (7.8ms RTL) - Is much better. There are *occasional* crackles, but I'm going to work at this setting and see how it goes.
- 256 samples (13.6ms RTL) - This is still very usable. I'm sure that latencies like this bothered me with the Delta66 (playing through an amp sim plugin). Maybe it's a placebo effect because 13.6ms is 13.6ms no matter which audio interface you play through - but others have reported that they're OK playing with latencies like this too. Anyway - there are no crackles or anything at this setting.
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The audio quality is great - although I'll pay more attention to this through the week when I actually use the Ultralite for tracking. I made sure I can return this interface "just in case" I had problems running a USB interface - but I think this is definitely going to be a keeper. I think the fact that I can't get the latency a little better is more due to my PC setup than the MOTU drivers or the hardware itself.
It also seems to be connecting to the web interface OK today too - but as you say Jim, it's easy enough to just type the ip address (from DHCP) in the browser, and that *always* works.
== I'll maybe play around with the DSP mixer and stuff sometime, and find out what "audiodesk" is, but for now I think this is going to work out well.
I'll report back later in the week.
Thanks again Jim for your input, and help. This seems like a good low latency AI.