I am seriously considering switching research groups. To be brief: I am a graduate student in condensed matter physics who had just passed the PHD candidate qualification exam. I have been working in my current lab for a year. I am unsatisfied with my working conditions in terms of interactions with my advisor and a senior lab member. I do not believe I am getting adequate feedback or direction from my advisor. The senior lab member is very difficult to work with but I cannot avoid working with him. I believe either reason alone is enough to start thinking about switching groups, but both combined make it very difficult to justify staying. My worries: I already switched once during my first semester, though for good reason. I do not want to burn bridges with my current advisor. How do I do this? Should I talk to the graduate coordinator first? What about my committee?