Is there anyway to boost the bluetooth signal so that i can be in the house with it outside?
Short answer - No. Bluetooth has an approx range, line of sight of 10M (33ft). This can significantly reduce due to walls and other obstructions. I have a Bluetooth Shunt in my car, am sitting in my caravan at a range of 2.5M and it won’t connect due to the steel of the car and aluminum of the caravan. 
Yes, you can get extenders, but they need to plug into the transmitter, which is in the AC2A and has no plug.