Narrative:

Once the aircraft was at the gate and all passengers deplaned we boarded and did our pre-flight checks. In talking with the inbound flight attendant; she mentioned that the main boarding door whistled so I should have earplugs ready. My pilots heard what she said and said they couldn't see anything wrong. We boarded passengers and closed the main door. All green marks matched and as I closed the door; using the door assist button; I checked once again to make sure I couldn't see anything that was abnormal. The door indicated closed in the flight deck and we took off. In flight I received the 10;000 foot chime and the door seemed normal and was not whistling abnormally loud. I got through my beverage service but when I came back to the galley I heard a loud buzzing/vibrating sound coming from the direction of the boarding door. I stowed my cart in the galley; picked up trash and by the time I got back the noise was loud enough to warrant earplugs. We were at cruising altitude around 30;000 feet. I pulled out my earplugs and put them in. I continued to check on passengers. About 50 minutes before landing the flight deck called and asked what the noise was. I told them and they said they could hear it through the interphone. The captain asked me to look at the door once again. I pulled the weather curtain away and when I did I happened to glance down at the bottom right side of the door and noticed light. At first I thought it was the reflection of light from a passenger's window or service door window but when I replaced the weather curtain the light did not change in brightness or shape. I relayed this information as well as the location of the light to the captain who said he would get back to me. The captain called me back and said that he had received a message that I should stow everything in the galley and move away from the door. Neither of us felt comfortable having me sit in my jumpseat for landing and together we deemed that in case of an emergency I could perform all necessary duties from seat 1B. It was at this time that we began our descent. We landed normally and made it to the gate. We waited until all passengers had deplaned and the captain; first officer and myself decided to write up the problem. It was ultimately decided that the next flight would be canceled and our aircraft repositioned back to our departure station the following morning.

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Original NASA ASRS Text

Title: A Flight Attendant aboard an unidentified air carrier aircraft discovered the main cabin door was improperly sealed although it indicated properly closed. Flight Attendant remained clear of the door and wrote it up for inspection and repair upon landing.

Narrative: Once the aircraft was at the gate and all passengers deplaned we boarded and did our pre-flight checks. In talking with the inbound Flight Attendant; she mentioned that the main boarding door whistled so I should have earplugs ready. My Pilots heard what she said and said they couldn't see anything wrong. We boarded passengers and closed the main door. All green marks matched and as I closed the door; using the door assist button; I checked once again to make sure I couldn't see anything that was abnormal. The door indicated closed in the Flight Deck and we took off. In flight I received the 10;000 foot chime and the door seemed normal and was not whistling abnormally loud. I got through my beverage service but when I came back to the galley I heard a loud buzzing/vibrating sound coming from the direction of the boarding door. I stowed my cart in the galley; picked up trash and by the time I got back the noise was loud enough to warrant earplugs. We were at cruising altitude around 30;000 feet. I pulled out my earplugs and put them in. I continued to check on passengers. About 50 minutes before landing the Flight Deck called and asked what the noise was. I told them and they said they could hear it through the interphone. The Captain asked me to look at the door once again. I pulled the weather curtain away and when I did I happened to glance down at the bottom right side of the door and noticed light. At first I thought it was the reflection of light from a passenger's window or service door window but when I replaced the weather curtain the light did not change in brightness or shape. I relayed this information as well as the location of the light to the Captain who said he would get back to me. The Captain called me back and said that he had received a message that I should stow everything in the galley and move away from the door. Neither of us felt comfortable having me sit in my jumpseat for landing and together we deemed that in case of an emergency I could perform all necessary duties from seat 1B. It was at this time that we began our descent. We landed normally and made it to the gate. We waited until all passengers had deplaned and the Captain; First Officer and myself decided to write up the problem. It was ultimately decided that the next flight would be canceled and our aircraft repositioned back to our departure station the following morning.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.