The DBUS is a communication protocol between applications. You can think of it as a way for one application to send signals to another. For instance it is used to send a pause signal to the media player when your phone rings.

I'm not sure what Yaspot used DBUS for, but I guess it might use it to communicate with despotify.

I've seen that error message a few times before with Yaspot because either Yaspot is already running, or you are trying to run it as root. To make sure Yaspot isn't already running, use the command

killall yaspot

in terminal (or reboot your device). To make sure you are not running as root, just don't write sudo gainroot before running yaspot.

Maybe yaspot is also using the despotify executables and not just the library. Just in case, make sure despotify is also the newest version by typing the following commands in terminal:

sudo gainroot
apt-get update
apt-get install despotify
exit

And try to run yaspot again.

Hope this works for you. Good luck