Wanting some help with MFP, Runkeeper and fitbit

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Currently I have runkeeper connected to MFP and then MFP to fitbit. What my question is today I did a 2.2 mile walk/run and the calories adjusted into fitbit and MFP but the distance was off by .7. Do you think it is because I have my stride off any suggestions. I love using runkeeper because it tells me my miles per hour and distance covered while walking. Thanks in advance for anyhelp..