Dialog, especially Shatner’s, can be muffled in the sound mix. For this, I used to think “Ensign” but now I hear “Benson.” I used to wonder why he'd say "Ensign" that way, and it's not the usual Shatner pause.
In Arena, I hear “Herlihy” but the cast list has him as “O’Herlihy.”
He also throws his emphasis around once in a while. During Journey to Babel, in the climactic confrontation with the Orion ship, he gives the order to cut power:
KIRK: Engineering, this is the Captain. Cut power on port side except for phaser banks. (they immediately cut power – Kirk is suddenly annoyed). At my signal --cut starboard power. Kirk out.
This sounded like they cut power on the port side before he wanted them to and then asked to cut starboard power. My sister and I even laughed because we thought it was tension-releasing humor. Then, seconds later:
KIRK: Engineering, cut power on starboard side. Maintain until further orders.
Which confused me as a kid because Kirk already cut starboard power. Or so I thought. Shatner just put a weird stress on “at my signal” instead of just saying it normally. Maybe Shatner was playing the pain of his injury, but as a youngster, I took it differently than it was intended.
The transcript sites can be wrong. They have Kirk and Carolyn say “bugs the percentages” in Who Mourns for Adonias? when it’s clearly and more sensibly “bucks.”