Numbers are getting Doubled, when 2 channels of IVR


I have developed an application which get the Input from the user like Date of birth.

exten => s,n,Read(dateofbirth,getDOB,8,s)

I have 5 channels (5 Phone lines) for the IVR system. I am getting the issue that the entered date of birth is mismatched. Once the date of birth has been entered, we will confirm the date of bith from the user that "You have entered "Zero, One, Zero, One, One, Nine, Eight, Zero (01/01/1980). Is this correct. Please press 1 for yes or press 2 for No. We have noriced and found that for some cases, the entries got doubled like 001101199. 0 (2 times) 1 (2 times) and 9 (2 times). We got compliant that the entered Date of birth not announced properly.

Our assumption is that the key stroke is getting doubled instead of once.

Also we have suspection that if 2 people are calling at the same time, and entering the numbers, can we get this kind of issues?

Please suggest and let us know how to rectify this issue.

Also let us know, if there are any configuration to arrest double key strock.

Thank You!

Ismail Khan A