Continuity mistake: Frasier discovers Niles' bird is dead and throws a dish towel over it. The next shot of the dish towel shows it has changed position, and the third shot shows it back in its original state. No one touched it in the meantime. (00:10:10)
Continuity mistake: Niles leaves the kitchen with a small tray of devilled eggs to serve his guests - as the shot changes to him coming into the dining area, he is carrying a different tray, with different appetizers on it, including some grapes. (00:08:35)
Continuity mistake: During the part of the show where they are getting ready to play Murder we can see empty punch glasses on the table - in another shot we see three even though no one went near them. This changes back to 2 after the lights come on - unlikely anyone helped themselves to punch when the lights were out.
Answer: It equals the record of James Arness of "Gunsmoke" for the actor who's played the same part on TV NOT in a soap opera. If you include soaps there are two main contenders - William Roache, who's been playing Ken Barlow in "Coronation Street" in the UK since 1960. Don Hastings has been playing Robert Hughes in US soap "As the World Turns" since 1960 as well.