Follow me - how to play busy signal when extension is busy?

I am running Asterisk 1.4 and Freepbx 2.4.

I configured “follow me” to play an anouncement after 30 seconds when extension 12345 is dialed.

Unfortunately the follow me announcement is also played when the line is busy.

How can i prevent this? I only want to play the announcement when the line is not answered for 30 secons.

When the line is busy it should play the busy signal.

Voicemail is also not needed/wanted.

Is this not possible with follow me?

Can i configure voicemail in that way (just announcement, no mesage recording, busy signal when busy)?