I have a client who are on a Domain controller with mostly windows machines and a couple macs. One user has a iMac running Darwin and I cannot get the internet speeds to reach their 100x10 twc circuit. I have tested on wireless and Ethernet with results best at 45x10. Troubleshooting I have done this far is test it strictly on Ethernet with wireless disabled and wireless without the Ethernet cable plugged in, checked duplex speed which is set to full, closed all applications and programs. I tested speeds using my windows machine on the same Ethernet cable the user uses an get the full 100x10. The other Mac users get the correct speeds but I cannot get this machine to get the full speeds. What else can I try?