Visible crew/equipment: When Rodney, Mickey and Jevon are talking after Rodney has just got a date with Nerys, the shadow of a boom mic moves across Mickey's face and body on multiple occasions.
Visible crew/equipment: When Del boasts about being a paratrooper, as Rodney says "You've made a few drops in your time", behind Rodney, a shadow of a crewmember or some sort of equipment moves behind him.
From Prussia with Love - S5-E1
Visible crew/equipment: When Rodney introduces the German girl to Albert, at the top of the screen, a boom mic passes Rodney's head.
The Jolly Boys' Outing - S6-E7
Visible crew/equipment: When the Trotters are in bed, look at the top left corner of the screen. A boom mic can be seen coming down and then going back up. Look carefully, its a dark scene.
Visible crew/equipment: When Del and Rodney are in Debbie's flat, Del and Rodney are talking about June not having a record player. A shadow of either a camera or a crew member are visible on the open front door.
Diamonds Are for Heather - S2-E8
Visible crew/equipment: During the dinner scene in the Indian restaurant, the shadow of a boom mic can be seen on the wall behind Del and Heather's table.
If They Could See Us Now...! - S9-E1
Visible crew/equipment: When Del is on the TV Show "Goldrush", he asks to phone Rodney to help him out on a question. As Rodney is watching the show and listening, you can see the camera reflected in Rodney's TV.
Miami Twice: The American Dream - S7-E8
Visible crew/equipment: When Del asks Rodney if he is still going to Miami after Cassandra says no, Rodney replies, "Possibly." As he walks off, you can see a studio light blurs the camera at the top of the screen in the middle.
Visible crew/equipment: As Miranda walks in for the first time, as Grandad says "some posh tart", in the mirror on the far lefthand side, the shadow of a boom mic can be seen on the reflection of the T.V., moving around. (00:05:35)
The Russians Are Coming - S1-E6
Visible crew/equipment: In the bunker, when Rodney asks Del to be serious for one minute, a boom mic can just be seen on the far left of the screen before it is pulled away. (00:20:50)
A Slow Bus to Chingford - S1-E5
Visible crew/equipment: When Del says to Rodney atop the bus about Janice not wearing a bra, a stage light is reflected in Del's drink. (00:25:10)
Visible crew/equipment: Just before Del gives Rodney his cup of half full tea, when they are in the middle of the sea, a boom mic is visible at the top of the screen.
The Unlucky Winner Is... - S6-E4
Visible crew/equipment: When Rodney is talking to Cassandra in the pub, the shadow of a crewmember/camera is visible on numerous occasions behind Rodney.
If They Could See Us Now...! - S9-E1
Visible crew/equipment: Just as Rodney says "Unbelievable", when he realises he was to blame, as the shot changes to Del, the boom mic is visible in the top right corner for a split second. (00:13:30)
Visible crew/equipment: When Cassandra is on the phone to Del at the start, a boom mic shadow is visible.
From Prussia with Love - S5-E1
Visible crew/equipment: When the German girl asks if she can sit down, whilst in the Trotter's flat, just above her head, a boom mic pops into view.
The Long Legs of the Law - S2-E1
Visible crew/equipment: When Rodney walks over to Grandad and Del, just after Grandad says "they are never off duty", a boom mic pops into view for a second and then moves back up again.
Visible crew/equipment: After Albert has filled up the baby bottle with the proper water, Myles, Rodney, Del and Albert are all back in front of the shed. In one of the shed windows, a boom mic can be seen moving around.
Visible crew/equipment: When Albert starts singing when he is drunk, a shadow of a boom mic is visible at the top of the screen.
Yuppy Love - S6-E1
Visible crew/equipment: In the very first scene when Rodney is working on his computer, you can see movement in the reflection on the screen. Obviously the crew getting ready to film.
Chosen answer: An apparent long string of illnesses.