Schiit Freya Thump or pop sound

Hi guys just a quick question for anyone ,I just purchased a Schiit Freya thats being used with Mcintosh mc452 and D150.Using xlr and each time I power off the unit I get this loud Thump sound through my Wilson Sophia 3 speakers.The thump also can be heard through my dual subwoofers .I love this preamp but that noise is annoying.Ive tried muting before power off ,volume is always set to lowest.Just curious if anyone else is getting this ,Thanks for reading .