Heat Pumps and Electric Heating - Heat Pump Question

I posted this in the wrong section so please forgive the duplicate posting. I have a question about the temperature coming out of my air handler. I have a 5 ton Ruud Achiever 14 heat pump. I have a digital thermometer monitoring the air temp exiting the air handler. When the unit first comes on the temp will rise and stabilize in about a minute, then it falls about 6 degrees. It will then slowly rise again in about 5 minutes to the original temp. I have the heat strips shut off so I know they are not the cause. It does have a variable speed blower but I can hear no difference in the air flow while the unit is operating. What would cause this temporary drop?

Hard to say for sure. How the duct work is where the cold air comes from and all that stuff. Also the TXV valve can be working then set's itself like.