Has anyone else had any problems getting a response out of TiVo Support??

I have had a tuner problem with my TiVo, and emailed support@mytivo.com.au 4 weeks ago to get some help. After an initial email from them (requesting some additional information, which I provided), I have got no response from them whatsoever, despite repeated reminder emails from me. I am getting increasingly frustrated, but am not sure what I can do!

Does anyone have any suggestions on how else I can contact TiVo to get some help?

Arrrrggghhh!!