USPS Shipping Module is Overcharging Domestic and International Orders

I did see that there was another person suffering from this but I don't think I have the same problem. I have noticed that my Zen Cart is overcharging my clients for shipping. One example: a 2 oz package from the USA to the UK has a USPS postage rate of $6.16, I add on a flat $2 for handling and the total my clients should be paying is $$8.16. However, my client was charged $11.45 a difference of $2.29 more than it should be.

My other particulars:
The module I am using is the USPS module 2013-01-27
When I go to Admin--config--shipping/Pkg--tare sm/med I get 0:0.125
All of the setting in that area are:
country of origin: US
Postal Code: 45226
Max pkg weight: 50 lbs
Package tare sm-med: 0:0.125
Larger Pkgs: 10:0
Display no of obxes and wt. status;3
Order free shipping weight status:0
Shipping estimator display settings for cart:1
Display order comments on invoice: 1
Display order comments admin packing slip: 1

When I go into admin--tools--dev tool kit and enter usps.php in the last box I get this:
*@version $Id: usps.php 18348G 2013-01-27 01:27:00Z ajeh $ on lines

I hope that the image at the bottom comes through, if not I will resend it. Thank you very much for your help in this.

The module I am using is the USPS module 2013-01-27

Latest is 27 Mar 2013
http://www.zen-cart.com/downloads.php?do=file&id=1292

4 ounces from the US to UK is $8.88 by my first class package estimator. Your 2 ounces ($6.16) plus the 2 ounces Tare (0.125 pounds). Plus your $2 handling = 10.88

That's pretty dar n close to reality. We use the extra to cover the occasional lost package or OOPS.

First: Thank You! As I am fond of saying (and it seems appropriate here) good thing it wasn't a rattlesnake. I read another thread on the subject but I think that one was written just after the problem was detected and a fix was not put in yet. Thank you for the point in the right direction. I installed it and tested it and it works like a charm. (snake charm).

I hear you, Rix Stix and I do indemnify my company by a small surcharge already (like an insurance policy premium which is tacked on to the cost of doing business). I have exceptionally price sensitive clients and I don't want them to think I am ripping them off. The new fix is spot on.

Again thank you all and sorry to bother you.

Glad that the update corrected your issue