Don't force the samplerate in the audiorate effect
Don't force the samplerate in the audiorate effect

reviewed by: Xavier Queralt
Fixes #1489

timvideos/flumotion,flumotion-mirror/flumotion,flumotion-mirror/flumotion,timvideos/flumotion,Flumotion/flumotion,Flumotion/flumotion,Flumotion/flumotion,timvideos/flumotion,Flumotion/flumotion