Slow programs

We are currently using team view to have our India design team run an internal software that requires our local server data base to run.  The software is running very slowly but only at certain times, paticularly between  1am and 5am EST.  The designers are working and trying to click in the program and the clicks are not even registering/ registering minutes later.  But other programs/ later in the day it all functions as expected.

What would be the solution to an issue like this?