Gabriel,
What type of issues are you having?
Could you start by checking the command
show port advertise port# 
See if these are the results you are expecting.
You may even want to try the command to see if there is a neg issue.
clear port advertise ge.x.x 
1000t                    Advertises 1000BASE-T half duplex mode.
1000tfd                  Advertises 1000BASE-T full duplex mode.
100tx                    Advertises 100BASE-TX half duplex mode.
100txfd                  Advertises 100BASE-TX full duplex mode.
10t                      Advertises 10BASE-T half duplex mode.
10tfd                    Advertises 10BASE-T full duplex mode.
                     
pause                    Advertises PAUSE for full-duplex links.
Jason