Sp Services not working with Https

Question

I have a Sharepoint 2010 installation. I am using Sp Services 2013.01 to get find if the current user is in a certain Sharepoint group. this works great if the url is not set to https. When the url is secured, the Status response from the call is error and the responseXMl is undefined. Here is an example of what I am doing:

var groupName = "My Group";
$().SPServices({
        operation: "GetGroupCollectionFromUser",
        userLoginName: $().SPServices.SPGetCurrentUser(),
        async: false,
        completefunc: function(xData, Status) { 
            if($(xData.responseXML).find("Group[Name='" + groupName + "']").length == 1) 
            {

                // Yes user is in group
                isUserInGroup = true;   
            }

        }
    });  

    return isUserInGroup;

But When the site is https it always comes back as error. This may not be a code problem and may be a IIS issue, but just trying to get some insight on what to look for check on.

thanks.