To disable these service alerts in the Direct Admin control panel, you can simply edit the file services.status at  /usr/local/directadmin/data/admin/

sudo nano /usr/local/directadmin/data/admin/services.status

This file should look (similar) like this:

#GNU nano 2.0.9 File: /usr/local/directadmin/data/admin/services.status
directadmin=ON
dovecot=ON
exim=ON
httpd=ON
lfd=ON
mysqld=ON
named=ON
proftpd=ON
sshd=ON

If you want to disable SSH alerts in Direct Admin, maybe because a spammer is trying to brute force its way into your system, simply change ON to OFF:

sshd=OFF

Now, for changes to take effect, restart Direct Admin with the following command:

/etc/init.d/directadmin restart

You now should no longer receive these updates from the selected services.