That does sound like a problem.

Check your saved flights, and delete any that have the 757 saved with them, and also delete the one that's checked to be your default.  Some weird issues get saved with your saved flights, even in the default and even if the default doesn't have the 757 selected.

Restart the sim and reload the plane and see if the issue still exists.

If it does, it's probably a botched install.  There's a KB about how to do a proper uninstall procedure.  Search for it and shut down the sim and then follow that.  Then make sure when you re-install the plane that your firewalls and antivirus softwares are disabled, and then do the re-install with the sim shut down.  With your firewalls and antivirus stuff still disabled, boot the sim, and it may immediately ask you to begin approving the trust relationships for various gauges and systems items, and it certainly should when you load the plane the first time.

A lot of times (especially on vista) these trust relationships and/or critical parts of the install process never complete due to vista's UAC and/or firewall/antivirus trying to think for you.

If those processes don't fix the issues, then I'd say certainly go to CS for a ticket.  They'll want you to go through all this before looking into it further, so make sure to do your due diligence on these items first.