As has been mentioned, we have had some bad power supplies. But, be aware that many power issues are beyond our control, such as bad AC, faulty power sockets, etc.
If you think that the problem is your power supply, it would be worth trying another one. Since your unit would appear to be out of warranty, it might be cheapest and easiest to buy another one from the Eventide Web Store. Otherwise, contact firstname.lastname@example.org.