It seems to be something lots of people experience. My therapist almost expects it and offers to make recordings on people's phones of his voice both as a relaxation tape and just for soothing and maintain a sense of constancy.

It also may not be something that needs to be viewed negatively or judged because it indicates that you seem to want and are trying to enter into the relationship and something about that is activating something like doubt or anxiety or fear.

You didn't say how long you have been with this therapist or if you have done therapy before, but my guess is that this is not a lasting issue. That it could get resolved or come and go with some patience and reassurance.