S60 > some sounds are low on volume

Hello,

i encounter a problem while testing my app on a s60 (3650 and NGAGE). Some Sounds converted from midi to OTA with the Nokia Audio Converter are very quite and low on volume. There must be a problem with the sound files. Because other sounds are working perfect. But our sounds are only simple notes without any volume programm change in it :(

On all tested S40 handsets the same soundfiles are all ok!

Any ideas why the sound are so quite
thanks

what methods are u using to convert the same..are yu making any changes in the pitch or the tempo by any chance?
ciao