I found a similar problem describes twice in the mail-archive, but there has been no answer.
I seem to recall having the same problem some time back.. I can't remember what the solution was but try deleting all the auxiliary files that LyX/LaTeX generates like .bbl, .blg, .aux, .dvi/ps/pdf, .tex and then try exporting/viewing from Lyx.. that may help..
nirmal
