Low tone beep/dings under hood

[Flippercon]

So I have only noticed this after the rbc swap. I dont know if it has always been there but after driving and shutting off the engine I hear a series of low tone beeps. Its like 4 or 5 beeps/dings. What is it?

 

[323]

Does it sound electronic or mechanical?

 

[Flippercon]

Does it sound electronic or mechanical?

Electrical