Do you want to remove everything after the 2nd last _ character? It's hard to know for sure with only two examples and no description of what you want removed.
thanks for your reply.
the downloads are from the bbc and are almost always the same format.
The_News_Quiz_Extra_Series_27_-_08._Episode_8 is the episode name
_m0009k92_original and m0009k93_iplayer are what i want to remove from the end.
I used to just remove the last 18 characters but the bbc changed the format occasionally and it had less characters and i deleted part of the name.
the format is always
The_News_Quiz_Extra_Series_27-_08._Episode_8_m0009k92_original.mp3
episode name _m0009k92 _original
what i was trying to do was find the second last _ and delete it and everything after it