Has anyone noticed any issues with the built-in keyer? When I first used it it often dropped the final dit of a character. For example, often C would be sent as K. Changing it to Iambic B seemed to fix this. However, I am still getting frequent occasions when it mangles what I am sending. I get the occasional funny characters with my Yaesu rigs so I know it's often my fault but it happens so much more with the QCX. I don't have an enclosure so it could be RF getting into it.
So, if nobody else has this problem then the fault is mine. But if others have this happen then it could be a firmware issue.