uffff buscar en google y que en el primer thread del ofi leas que no hay una solucion clara al problema.
edit: me ha parecido tan raro que he estado buscando.
There is a work around for this. Not sure where the thread went though give me a few mins and I'll type it out.
How I fixed this on this exact router.
1)Open the router page generally 192.168.0.1
2) Log into the router
3) Click the Advanced Tab
4) Select Application Rules
5) You will need to manually add these settings: ((The third one is 6881-6999, I know the photo cuts of the last 9 ))
http://i303.photobucket.com/albums/nn140/totalil1/RouterD3settingspage1.png
6) Click Save settings
7) Once save head Back to the Advanced tab
8) select Firewall settings (( I know this causes security concerns, but its way better then DMZ ))
9) Make sure you settings Mirror these:
http://i303.photobucket.com/albums/nn140/totalil1/RouterD3settingspage2.png
Fixed the problems I was having. Depending on your modem you may also need to dissable its SPI filtering.
Sorry forums wont allow me to link or image put just copy link to go to image.
Also please like if this helped