[Timo]

I think it may be more to do with the limitations of the hardware that Access implemented elsewhere.

There are three different types (speeds) of USB v2 chipsets:-

1) Lo Speed = 1.5 Mbit/sec (187.5 KByte/sec)
2) Full Speed = 12 Mbit/sec (1.5 MByte/sec)
3) High Speed = 480 Mbit/sec (60 MByte/sec)

Access chose to use the Full Speed chip. So the TI's USB connection is limited to 12 Mbit (1.5MByte/second) - for everything.

Streaming a mono track at 44,100 Hz 16-bit would require 86 KByte/second.
(16-bits = 2 Bytes, therefore 44100 x 2 = 88200 Bytes = 86.13 KBytes).

Access allow six audio channels, so 6 x 86 KB = 517 KB/second (0.5 MByte/second).
Factor in streaming MIDI, Virus Control, VST automation data, Remote control, and error correction, and it'd probably not be far off from using up most of the 1.5 MByte/second bandwidth available.

That said, streaming a mono track at 44,100Hz 24-bits would only require 129 KBytes/second.
(24-bits = 3 bytes, therefore 44100 x 3 = 132300 Bytes = 129.2 KBytes).

Six channels of 24-bit would need 775 KByte/second. Which is only 258 KByte/sec more than six channels at 16-bit.

I'm unsure as to how much bandwidth MIDI, VC, VST, Remote, and error correction require.

If it were me, I'd try plumbing your Ti into your 192KHz/24bit soundcard for recording at 44.1KHz/24-bit, and use the TI's USB for MIDI/VC purposes. You can always try it yourself and see if the added fidelity of that setup is noticeable or not.