I found this information about the robellini - I am NOT an expert but thought this sounded like it might be your problem...
the robellini palm usually is disease resistant, you may have another problem Manganese deficiency, in particular, causes new fronds to appear yellow, withered or scorched; the name for this is "frizzletop". It is a common problem for palms in south Florida and can be controlled by using manganese sulfate. It frequently occurs in palms growing in soils that are extremely alkaline, so you may also need to adjust the pH of your soil.
Here is the link:
http://en.allexperts.com/q/Plant-Dis...llini-Palm.htm