the service is provided by
shairport-sync (that we pull from Raspbian testing), so if you do:
sudo apt-get remove shairport-sync
then it will definitely stop the service, though there are other ways to do it (such as disabling the service on boot while keeping it around to be started manually as needed).
... after that, make sure the
rate value in
/etc/asound.conf is appropriate for what you wish to do, or take the
rate completely out of file (which in theory should then hand over the control of rate switching to ALSA, which may allow more flexibility.