Vibrate issue

Ok I just had a question I just noticed when I put my phone on vibrate you can still hear sounds sometimes.
I think I only noticed it on Twidroid Pro and eBuddy I had my phone on Vibrate and it still was playing sounds.
Is this a DROID problem or Software problem? I haven't investigated yet to see if any other apps do it.

Go to menu>settings>sound & display>Ringer volume

check the box that says "Use incoming call volume for notifications"

Thant should work.

sweet thnx

its selected hope it works