Acting “too professional”

I recently received some feedback about how I interact with clientele.

Not terribly long ago my boss at work described a lot of my interactions with clients as very “transactional.” I usually try to put my best, most professional demeanor on with every client I work with in every situation as it is how I was trained throughout college (very formal music conservatory). I also live in a very affluent area, where the median income is high and we serve a lot of high class individuals.

I explained this to him but his response was “I get that man, but you sound like an automated kiosk.” it has me self-conscious now, I have to question if some job interviews for positions I did not get were because of this. Hell, the longest lasting jobs I’ve had were the ones where I’ve described the interview as going “terrible,” but looking back I only described it as such because it felt too casual. I felt like I wasn’t dressed right or I didn’t speak formally enough….looking back, it was probably because I was acting like a person rather than a robot.

Perhaps I can reverse this, what are some traits that are often seen as being “too professional” or “transactional” or “soulless” or however, people want to describe it.