Possible Clues:

• Set out in ship, I hear
• Starts to see the eels in large ship -- one's likely to catch a lot
• Having left, is about to catch up, one hears
• Auditor finally hears half of text on board ship
• Member of the radio audience
• One who might lend you an ear
• Ship concealing most of gun, I hear
• One paying attention to line from translated entries?
• One paying attention to line from wrong entries
• One picks up tip: nurse on medical programme