I'd like to find a multi-channel PC sound interface with 8 discrete, line-level analog inputs (7.1), and capable of at least 96/24 sampling rate (192/24 would be even better). Any specific recommendations? I'm leaning toward something that uses a USB interface and external box to keep analog audio signals outside of the noisy environment inside a PC.

I had thought about something like the Tascam US-1800, but that appears to only have balanced mic inputs, not unbalanced line inputs.