From the Scarlett 2i2 User Guide ...
"Using Direct Monitoring
You will frequently hear the term “latency” used in connection with digital audio systems. In the case of the simple DAW recording application described above, latency will be the time it takes for your input signals to pass through your computer and audio software. Latency can be a problem for a performer who wishes to record while monitoring their input signals.
The Scarlett 2i2 is fitted with a “Direct Monitoring” option, which overcomes this problem. Setting the front panel “Direct Monitor” switch to ON will route your input signals directly to the Scarlett 2i2’s headphone and main monitor outputs. This enables you to hear yourself with zero latency – i.e., in “real time” – along with the computer playback. The input signals to your computer are not affected in any way by this setting.
When “Direct Monitoring” is set to ON, ensure that your DAW software is not set to route its input (what you are currently recording) to its output. If it is, you will hear yourself “twice”, with one signal audibly delayed as an echo."
Hope this helps.
Edited by Dad3353, 24 May 2015 - 03:32 PM.