Blinking OSD problem on an e228WFP

About a week ago I received a new Dell computer, with the e228WFP monitor. all had been working fine, until today in the afternoon, the OSD on the e228WFP started appearing & disappearing at random. Also, it looks like the monitor control buttons are not working. I did, for a while, also have the "locked OSD" problem, but that has now disappeared. I have read a number of posts on re-setting the "locked OSD", but none of that has helped the problem with my "blinking" OSD. I have tried unpligging & re-plugging the power cable & the DVI cable, but none of this helps. Any ideas about how to solve this, or do i have to get a replacement monitor (which would be a major pain). Thanks in advance (and apologies for typos - the OSD keeps flashing all the time, so occassionally I can't see all the text)´.