Balance 50 speed issue

I am working with tech support on this and they are sending it to engineering but while im waiting I thought I would try here
I am going to be putting this in for a customer and here is what the issue is. I have one dsl (at the customer site I will have 2) and when I do a speed test I get 3 megs down and 8.5 up. I take the same cable plunged into the was and plug it into my laptop and I get 40 down 9.5 up. they have looked at it and don’t see any issues. any ideas?

Issue: Slow speeds directly connected to the Balance 50
Resolved: Customer figured out his NIC on the PC was set to 100 full duplex and when set it to auto the problem went away.