How I would respond would be dependent upon several factors:
How many complaints have there been, and do they relate to the same thing?
If you have several people commenting on a similar thing then it becomes helpful to look at yourself to see what it is about how you interact with people that fosters this response. Then you have a choice… to think well, this is who I am, and I will connect with people honestly this way, and the ones who don’t mesh well with me will find someone else to work with. Or, you might say… hmmm… this is a communication style that I can see has a potential not to work well, and it is something I will take some time to rethink.
I like the quote that half of communication is listening. And listening is not just waiting for the other person to be done so I can talk again. Seeing how what we say is taken and thinking ‘how can I best put my message so it is heard’ are great skills.
Also, Who is complaining?
How one might respond would of course differ if it were a student, a client, a coworker, or a superior. When dealing with people whose job it is to review me I have always started by telling them I hope they will let me know if they see ways I can improve. A lot of people hate giving performance reviews because they hate people getting their backs up. Being open to finding ways to improve oneself is a great way to build a good relationship with one’s supervisors. With coworkers it can be tricky. If a coworker complains about you it could be jealousy, or jockying for position, or differences in communication styles, or they could have a concern that is valid. But it will always give weight if there are more than one person noting something.
Documenting things can be helpful. If something ever were to escalate it is useful to have a paper trail…. and it is a reminder that it is important always to maintain professionalism in whatever interactions one has.