Swiped Magnetic Card Data Altered on one iMac and not Another

Anyone out there familiar with USB magnetic card readers and why an iMac would alter the swiped data? Any help would be so greatly appreciated! We just set up our Lightspeed Cloud POS system on both of our iMacs using Magtek Dynamag card readers. One computer is a mid 2011 21.5" and one is a late 2012 21.5" both are running 10.9.2. The mid 2011 has worked fine from the start with both card readers, the late 2012 doesn't work with either one. After many phone calls back and forth with Lightspeed, MerchantWare, and Magtek we've found out that it's a software issue but no one in tech support is familiar enough with OS X to figure out how to fix it. When you open up Word or TextEdit and swipe the card it gives you a long string of letters and symbols from the card read. On the 2011 (working) computer there are two ^ signs that appear before and after the card holder's name. On the 2012 iMac those "^" symbols show up as "&" instead and is causing the card read error in the POS. I know it's not a hardware issue because a) the reader works on the 2011 and b) we have Parallels running on the 2012 and when you connect the reader to the virtual machine and swipe the card in Notepad the card read shows up with the correct "^" symbols. We tried slowing down the card reader speed but that also didn't fix it. Basically, does anyone know why or how the 2012 iMac is changing a two out of three "^" symbols to "&" signs from a USB card swipe. Tech support mentioned there might be an incorrect USB keyboard setting somewhere but wasn't sure. I've tried to compare the settings on both computers side by side but can't find any differences between the settings. I'm stumped!