My go to contact method is phone and that works every time in my experience. Email is not reliable for a variety of reasons and usually a single phone call can cover a string of emails which can take multiple days to go back and forth. As someone who has been at both ends of the service issue and phone calls get the job done quicker and the personal approach always results in a happier customer. I had a major issue with an international customer and phone calls solved the problems and are way cheaper than a pissed off customer. I have never failed to resolve a problem when I can talk to the customer. If I ran a service dept such as Festool as soon as the tool was received the first thing that would happen is that the repairing technician would call the owner by phone to confirm the story to avoid any confusion about what is required and that assures the customer he or she is being looked after and customers value that sort of communication. I used to make sure that any communication with me whether for sales or service always resulted in a phone call within hours to start the process of support. Call me old fashioned but phone calls create a trusting relationship between the customer and the company that takes a lot to destroy, Lee Valley is an excellent example of how CS should be done.