Activating DSL modem firewall kills speed

[typer164111]

I want to use the firewall in my Westell 6100 DSL modem because I've heard that hardware-based firewalls are better than software (on a Mac, system 10.6.2), but if I even put it on minimum security instead of none my connection drops to a crawl. Westell won't give me any support because they say the model I'm using was designed especially for Verizon, and Verizon is therefore responsible for technical support for it. What's going on, and what should I do?

[dslr595148]

#1 What does Verizon say about it?

#2 How about the low level, does that kill your speed?

#3 Did you put the Westell 6100 into bridge mode?