[EAS] Is there a way to run an EAS crawl without audio?

[suzanne at mab.org]

I hope you techie types can answer a question for this non-techie policy wonk.  One of my stations wants to know, "are you aware of any Stations that use software that allows warnings to be displayed as a *silent* crawl at the bottom [sic - I think he means top] of the screen?"
 
Is there possibly a setting in the EAS box that accomplishes this?
 
Thanks,
 
Suzanne Goucher
Maine Association of Broadcasters