2010 ES 350 Navigation voice not working

[EM350]

Hi everyone, the voice on my navigation stopped working.  Anyone know how to fix this?

[RX400h]

Have you tried turning off and then starting your vehicle? 
Based upon what I have read, if the condition remains, check or have someone the 30-amp fuses in the engine bay fuse box. If they are good, the amplifier may have failed.

[EM350]

Thanks RX400h, but wouldn't  I have a problem with the radio if my amp was bad?  My radio works fine.  The only problem I'm having is with the navigation voice.