Long load/connection issues?

When I load up FTB it takes anywhere from one minute to five for the launcher to load up (staying at a white screen the whole time).

I've had the issue before and last time adding it to my anti-virus (Avast) exceptions list fixed the issue but nothing has changed there and now the issue is back. I have followed the basic troubleshooting guide to no avail.

Any assistance would be greatly...

Long load/connection issues?