talk to hear own voice
talk to hear (the sound of) (one's) own voice
1. To speak about useless, pointless things; to talk without purpose. Look, this stuff is important, guys. I'm not just talking to hear the sound of my own voice. When kids get to their teenage years, they act like their parents talk to hear their own voices.
2. To speak in an arrogant, boastful, or egotistical manner. Every single week the boss calls us into the board room to have a team meeting. It's supposed to be so we're all on the same page, but really she just talks to hear her own voice. I've had a few professors who loved talking to hear the sound of their own voices and who got positively irritable whenever you challenged them on something.
talk to hear one's own voice
Fig. to talk far more than is necessary; to talk much, in an egotistical manner. Oh, he's just talking to hear his own voice. Am I just talking to hear my own voice, or are you listening to me?