need to filter out note off message

this is probably very easy to solve, i have read tutorials and asked my fellow students. so forgive me for asking on the forum.

i have a key message going into a selector (ex: sel 41, to play a spesific sample via spesific key) the message then goes into a player which triggers a sample. the note on message triggers the sample, but the noteoff message also triggers the sample when i release the key.

so the question is: how do i stop the noteoff message from being transmitted with the noteon message.

i might have missed out on some fundamental programming, but can someone point me in the right direction

ps. have tried to divided by 127 and then pack 0 - 000, this works on a synth, but not on this one.

cheers

Arne