One thing that must be kept in mind is that if there is any free acid left in the amine salt, it will decompose some sugars to a brown tar-like mess.  Did you make the HCl salt of the psychoactives yourself or were they purchased in the salt form?  If you made the salt yourself and didn't use proper purification techniques, there is a very good chance that this is the culprit!

The dihydrochloride salt form was purchased.