This sounds not unlike the TASCAM US-800 issues that folks have with Win7. In order for Windows 7 (doesn't matter the application) to 'see' the interface, you have to power it on AFTER Windows 7 gets through boot. Then Win7 recognizes the interface and it will switch over to that as the default interface for any application using audio, if you've set it as the default interface. Then things are fairly happy.

There's no proper power switch on the unit and it does require a wall-wart, so I've bought a power strip to use as the power source. I've almost trained my brain to remember to power it off when I'm done, but not quite yet!

So, I'm wondering if you might have similar luck if you follow this sequence:

1. All power is off, PC and interface
2. Power up PC, allow Win7 to boot fully
3. Switch on the Focusrite by plugging in the USB cable
4. Start up BIAB (after you had left it using ASIO for the Focusrite in a previous use)

You might find that you have to do this for each of the USB ports that you might plug in the Focusrite - that is the case with the TASCAM US-800. It needs to get the driver associated with each USB port in some fashion. Also assuming you are not using the Focusrite through a USB hub - that can cause issues as well no matter what the USB audio interface is.

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