Have you unlocked it? https://forums.whirlpool.net.au/archive/1216321
I unlocked mine years ago and it opened up a lot of settings. But It is a very limited modem though after being unlocked (most ISP issued ones are), I would suggest buying your own. I upgraded from that modem to a Billion 7800N and my connection went from 1000KB/s to 2000KB/s just buy playing with the settings (SNR mainly) in the modem.