Continuity mistake: Roz has just received a call about Marty's missing chair and as Frasier comes into her booth, she is writing it down. As she says "I found the chair", she hands him the paper - but she goes from writing to handing it to him with no time in between. (00:16:35)
And the Whimper is... - S1-E18
Continuity mistake: At the awards ceremony Frasier is being introduced to his rival Fletcher's mother. At one point Fletcher is holding his mother's hand but in the next shot their hands are nowhere near each other.
Continuity mistake: Frasier is at the dining room table with Niles looking at Niles's childhood journal. He has his left hand ready to turn a page but in the next shot his hand is on the table, with no time for a natural shift.
And the Whimper is... - S1-E18
Continuity mistake: Early in the show, at Cafe Nervosa, Roz comes in and Bebe asks her to get her some coffee. Roz returns with a paper bag which she puts down on Bebe's right. In the next shot Bebe stands up with it in her left hand, but there was not enough time for it to change from the right to the left naturally.
Continuity mistake: Niles is leaving Frasier's with Daphne and as he says "it was a warm and friendly place", his raincoat strap goes from sticking out from his shoulder to lying flat on his chest.
Continuity mistake: When Frasier and Niles are in Cafe Nervosa, just as they are talking about Stanley Barrister, Frasier lays his hand on his knee, but in the next shot it is up on the table.
And the Whimper is... - S1-E18
Continuity mistake: Just after Roz puts Bebe's bag on the table at the Cafe, we see her back at the counter - there was not enough time for this to happen naturally.
Continuity mistake: While Frasier is driving, Marty has the map on his lap. During this scene the map changes appearance and size from shot to shot even though Marty never opens it up.
Continuity mistake: In the scene where Frasier and Niles are talking in Cafe Nervosa, the position of Niles hands and arms change a couple of times. At one point, while Frasier talks about the young woman he has met, Niles folds his arms in front of him but in the next shot to Frasier, we can see Niles fingers laced together - and then the shot returns to Niles with folded arms. They stay this way until another shot where he says "You were in a mall?" and his hands are suddenly on the table and one is lying over the other.
Frasier Crane's Day Off - S1-E23
Continuity mistake: Martin and Frasier are having breakfast and Marty is making fun of Frasier's radio audience. In one shot Marty's arms are folding on the table in front of him over his newspaper - in the next shot one arm is stretched out over the newspaper and the other is at 45 degrees angle in front of him.
Guess Who's Coming to Breakfast - S1-E13
Continuity mistake: Marty, Elaine, and Frasier are sitting down to breakfast. Elaine picks up her mug and in the next shot we see her reach and pick it up again.
Continuity mistake: While Frasier and Niles are having coffee outside at Cafe Nervosa, a red napkin is by Frasier's cuff. In the next shot it is suddenly in the center of the table, even though no one touched it.
Continuity mistake: In the episode "Call Me Irresponsible" from season 1, Frasier and Catherine are making out on Martin's old chair, which starts vibrating (probably because they inadvertently hit a switch on the side). But in "Give Him the Chair", Frasier tries to replace Martin's old chair by buying a new one which has a built-in massager. When Martin tries it, he looks horrified and says "That's disgusting", even though his beloved chair had the same feature.
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.