Honking Bypass valves?

[JShadzi at aol.com]

    A few months back I put a Bosch type Bypass valve in 80qt.  I have it 
rigged in a stock type installation.  Ever since installing it, I get this 
"honking" sound between 0 and 5 psi or so, or only at part throttle.  At WOT 
the sound is not there, and above 5 psi or so it goes away.
    My feeling is that the valve is cracking open, and in doing so lets a 
small amount of air past the diaphram, causing it to resonate and flap-making 
the resonating honking sound.  Have any of you ever experienced this problem? 
 It makes part throttle driving  very annoying, it feels like there is 
something wrong with the car, when I know there is not.  TIA,
Javad Shadzi
80 quattro turbo