And they start with the 2nd song. Thus, as a result the first song you have in the song UI is not sung until 9 seconds into combat. 

 

 

Edit: to be clear I'm talking about the start of combat only. 

Edited March 17, 201510 yr by Bazy

I think the delay between starting to chant again after an invocation is meant to be 2 seconds

I didn't even know there was a delay after invocation.

 

But I'm talking about the start of combat. They do nothing for the first 4 seconds after entering combat. 

Edited March 17, 201510 yr by Bazy

Seems like a bug