Possible Clues:

• Not a matter of course for a doubter, by the sound of it
• A large number inside will get a late meal
• Seems there might be no dout about it of course
• Eat it in the red inn
• Eat it in the strange red inn
• What, by the sound of it, no doubter 15 across
• Turn red around the hotel as a matter of course
• What feeds duke, and this man?
• The opposite of a doubter, as a matter of course, by the sound of it
• Sound of no doubter as a matter of course