I did a new install just the other day, it included a 1000 plus with a 722k and 222k receiver using a 44 switch. I had the 722k in port 1 and I verified which line I had my power inserter in for the switch. I know it worked when I left the customers house because we were watching all the different channels during the customer education.
Later that night the customer has to call dish; both his receivers were not getting signal. The csr for some reason sent an RA for the 722k. The next day I find out that I had a tc12 so I got the work order for it. I went to the customers and checked my lines, checked the outlet again and verified my signal with my super buddy on all 4 lines. I checked every possible section of line from the receiver to the switch to the dish. It turned out to be the 44 switch. It was brand new so I wouldn't think of it as being that, but it does happen with new switches as well as lnbfs and receivers.
It really upsets me when everything is new and you expect it to go in without a hitch. I know there is always a built in percentage of equipment failure for equipment, I just hate it when I get that bad batch of equipment and the thing goes out after I have left the install.