[Speex-dev] question about coding

[Leonardi Andrea]

Hi,
I'm trying to encode a raw audio file with speex. No problem if I normally decode it (as done in the samplenc.c, for example).
But if I separate odd and even samples and I try to encode separately these two files (one is [odd odd odd odd..], the other [even even even even..], then when I decode and I join the samples in one file [odd even odd even odd even..] I heard a terrible white noise, and the voice in background very weak.
Does anyone know the reason?
Thanks