Hi everyone- hope someone can help me with the following problem: My son usually gets a strong enough signal to make calls (at home, on the road, etc..), unless he is on campus, here in Miami, Florida (hot 5 months out of the year!). On campus, near any of the buildings, he is unable to get a signal, while many other students in and around the campus building are on their cells making calls. When he walks maybe 150-200 feet away from any of the buildings, he gets a signal. His carrier is T-Mobile. We took the phone back to T-Mobile a couple of months ago, to explain the issue to them, and they replaced the sim card and reset the phone. No improvement with the new sim card. Can anyone assist? Thanks!