Good afternoon and thank you for your inquiry. This is normal, as when
the receiver first turns on or initiates audio, the signal is sent to
the sub causing the chirping/burp noise.
I hope this helps.
Originally Posted by jvgillow /forum/post/14299528
Wow their reply told you absolutely nothing about why it makes that noise.
But yes that is normal behavior for them. The question has come up on AVS a few times before but I forget what the technical reason is for the chirp.