Originally Posted by ETalk
Have you run the "Mix Control" software that came on the disc with your interface?
This is key to your Scarlett interface being set up and working properly.
Also, I recommend contacting Focusrite Support about this issue. They will answer fairly promptly (depending on what time-zone you live in)!
Once you've done this then follow the Mix Control manual for setting up with your DAW (Reason).
Make sure that your latency is set to the correct settings for your computer's set up. If you're running a high end audio PC or Mac then this wont matter but if you're like most people then this will matter.
In Mixcontrol's panel look to the lower right and you will see some red writing. Set the Sample rate to 44.1kHz, Sync Source should be Internal, Sync Status-Locked and driver-connected.
Below this there is a settings button. If you're running an average computer then set the Driver latency to medium or long or your computer will not be able to support audio properly and your audio drivers will stop working. Asio buffer size should be 256-512 ideally but again depending on your PC you might find it happier with a higher buffer for playing back audio. For recording you will need to lower this buffer (in Reason) so that you don't get latency or lag with your tracks. The buffer settings in Mixcontrol should match up with the buffer settings in the audio preferences in Reason. Mixcontrol is like the central control room for your Scarlett!
This is by no means a full tutorial on how to use your interface in Reason but hopefully it'll get you started in the right direction!
PS. I use the Focusrite Saffire Pro 24 and I'm showing you the same procedures, might not be the same...