Is There in Truth No Beauty? - S3-E5
Visible crew/equipment: When Kirk turns to follow Miranda across the arboretum, the camera shadow is briefly visible on the wall at the lower left of the screen. (00:29:50)
Visible crew/equipment: A camera shadow briefly intrudes on the right side of the screen as Kirk asks Mr. Scott about the sensor readings. (00:00:55)
Requiem for Methuselah - S3-E19
Visible crew/equipment: The monofilament line holding M-4 aloft is visible in the lab when the floating robot delivers the processed ryetalyn to McCoy. (00:17:20)
Visible crew/equipment: In the very beginning, the boom shadow is visible at the top of the screen as Kirk walks to Spock's station on the bridge. (00:00:30)
Visible crew/equipment: When Kirk is agonizing over the sound of Surak's supposed cries for help, an equipment shadow, possibly from a boom mike, skates across the rocks behind his left shoulder. (00:40:00)
Visible crew/equipment: After Uhura asks McCoy if she'll become like Chekov, McCoy reassures her about finding an antidote. Then, when it cuts to Engineering, there's an actor's black tape mark and a chalk T-mark visible on the floor. (00:38:10)
Is There in Truth No Beauty? - S3-E5
Visible crew/equipment: Spock and Dr. Jones carry Koldos into his quarters, and when Spock walks over to the wall communicator to contact the bridge, the camera casts a shadow on the wall as it moves closer to Spock. (00:05:20)
Is There in Truth No Beauty? - S3-E5
Visible crew/equipment: At the dinner, when Miranda stands up to leave, there's a visible white tape mark on the floor near her feet. Then, when McCoy makes his exit Kirk reaches for the rose, and there's a better view of the white tape mark under the table. (00:11:50 - 00:13:45)
Visible crew/equipment: The shadow of a boom mic is seen against the rock walls of the cave follows Spock and McCoy when Spock pulls McCoy off Zarabeth.
Answer: Kirk was getting his physical and Dr. McCoy probably turned off communications, because if he hadn't, Kirk would have left and headed straight for the bridge, leaving McCoy irritated.