Issue? - speaker tweeters crackling when integrated amp turned on/off, muted/unmuted

AudiogoN Team,

I have a new Peachtree Nova integrated amplifier that I have hooked up to some older Boston Acoustics speakers (as I wait for the new ones that I have ordered to arrive).  I am hearing the following crackling / popping from both of the tweeters when the integrated amp is turned on / off and muted / unmuted:

- When turning on, sometimes get a single soft crack, sometimes not
- When turning off, get a louder cracking sound followed after a slight pause by a soft cracking sound (always 2 cracking sounds)
- When muting get a single louder cracking sound
- When unmuting, get a single soft cracking sound

Compared to the volume of the music, the cracking sounds are quite a bit less magnitude in loudness.  In between songs, the amp is perfectly silent and I don't notice any cracking sounds when playing music only during the on/off & mute / unmute actions.

All the connections seem to be well made and I stripped off new material on the cables before attaching them to the amp (bare wires through stud holes with nuts tightened) and speakers (bare wires clipped in when plastic tab is depressed).

Is this cracking / popping noise from both of the speaker tweeters normal during on / off and mute / unmute actions? 

Will this injure the speaker tweeters over time?     

Thanks in advance for your thoughts.