Possible Clues:

• Klink's rank
• Bogeyman
• Potter of "M*A*S*H," for one
• Commander
• 'No cello for this officer, strangely (7)'
• 'It's rank at the heart of the nut, by the sound of it (7)'
• Sounds as if one is in the middle rank
• By himself in the pass, it sounds as if he's at the centre of things
• High-ranking officer
• Does rank enable him to be at the heart of thigs, by the sound of it?