I just replaced the AirPort Extreme 802.11ac with the AirPort Time Capsule 802.11ac and it has much weaker Wi-Fi signal strength. I got 3 bars on my iPhone in the basement with the AirPort Extreme and now I only get 1-2 bars with the Time Capsule. The Time Capsule is placed exactly where the AirPort Extreme was on the second floor. Would this be considered normal due to interference with the hard drive in the Time Capsule or should I try exchanging it?