Weird noise from Minolta C451

Strange noise while turning on printer:
http://www.youtube.com/watch?v=eat8diO9i1c&feature=youtu.be

same noise while printing:
http://www.youtube.com/watch?v=i7ETqbRtWi4&feature=plcp

Sounds like some kind of plastic is touching some cog wheel or roller. Really can't define is it something near multipurpose tray/fuser side or in the middle where imaging units are, but visual inspection of those parts didn't get me any clue... It started after drums were reset and transfer roller & fuser cleaned from paper dust by minolta technicians.
Prints are OK but the sound is really annoying

 

problem solved. black toner was full of little toner balls & clusters so the toner input mechanism (somekind of cog wheel) between toner cartridge and drum wasn't working well. little vacuum cleaning of that place and changing toner cartridge helped

 

Was the same noise ?
https://www.youtube.com/watch?v=8UF25I4ACgc
your youtube clip are not available anymore.

 

Nope, not that kind of noise. It was years ago so I don't have that video any more :-(