If these are the ones advertised as having a 2-mile range, I'd take em back to the store and either get a refund or another set. At least one of the ones you have is defective.
The 2 miles is a marketing exaggeration, only achievable under ideal circumstances, but you should have no problem with a hundred yards, even with a few normal walls in the way.
If for whatever reason they're not returnable, you could trying opening them up to see if there are any obvious problems, such as the antenna not being connected.