Probably it isn't a bug, maybe audio isn't set up properly.
Most likely you have to start Qjackctl and
start it and make the desired connections with the applications you want to use for example Hydrogen and Zynaddsubfx (after you started them up).
For multiple recording on different tracks you could install Ardour it will give you much more possibility's to expand recording possibility's and improve them.
For midi you also have to set that up depends a little on your soundcard.
All these things isn't really hard and works very well on Elive, but if it is your first time it could help you to search a little bit on the net to get the best out off the different applications.