Thanks for you response. Sounds like a pretty involved repair for a home only 10 years old. I am assuming the vent and stack you refer to is the vent that should be in the wall on the second floor hopefully) and the stack is the pipe that goes to the attic and out the roof? Please understand I am a new homeowner so some of the terminology is new to me. Also, any suggestions you can offer to me in how to screen/interview plumbers that could fix this problem would be much appreciated. I am the wife who understands home repair to a much greater extent than my husband. Lastly, if this problem is not addressed, could further damage occur over time?
You can talk with neighbors and friends about plumbers that do a good job and guarantee their work. A phone call or visit to local plumbing supply companies may get some references about their better customers. The banging can potentially break pipes, but the noise is nothing to tolerate at night.