I have a magic mouse on my Ubuntu 14.04.2 system. It works pretty well, except it disconnects for no reason, and reconnects a minute later. Unsure why this is occurring. I changed the batteries in the device, and it works fine on my mac.
I had a similar(ish) issue with my wifi and had to disable a power saving feature. Could there be something similar with the bluetooth adapter?
lspci -nnk | grep -iA2 net
to your question as it might be a problem with bluetooth coexistance