If you don't want a lot of trouble trying to find out what's wrong, don't use a trs plug. Get yourself a cable with xlr (for mic) on one end and a 1/4" mono, ie, ts plug on the other end (for the Tyros). There has been a whole lot of stuff posted recently by LeoD about all the problems he was having. I have several xlr to mono 1/4" cables and they work fine.

Tom

Mono cables work just fine. The input is hot enough to handle a direct connection as well. No transformer is needed.