I have two clients whose websites appear to be cutting off the left side when viewed on a mobile phone. Here are the sites.
www.alertamericaar.com (this one is really bad)
www.camoillusions.com (this one just cuts off the edge of the page)

I have a half dozen other sites and none of them do this.

Using Xara Web Designer MX Premium. We always use the 955 pixel page setting. Changing this setting has done no good.