I was throwing a rough ballpark with "like a 100 times".
The lengths suggested for melodic chip instruments are all powers of 2 and they stay in tune because of that. Following that pattern the power of 2 closest to 32000 is 2^15 = 32768. But this method is of course limited to samples you generate in MilkyTracker and to answer your question, "
Is there a way to tune my percussion instruments in Milkytracker?":
Yes, you can tune your instruments
(actually each of the possible 16 samples inside an instrument individually) in the Instrument Editor. Click
Ins. Ed. and use the
Relative note buttons to get the ballpark and then the
F.tune slider to... finetune it.
There are frequency restrictions to keep in mind when you adjust the relative note of sample. This function is generally meant to set all of your instruments in tune and you will run into playback problems across different players when for example you have natively low frequency sample and you try to make it into a high pitched one by simply setting the relative note high. If you want to use a natively low frequency sample at high pitch or vice versa, resampling is recommended.