Navi worked before or no? Looks like navi soft is corrupted after not correct soft update...
1. Download the navi soft (v22 o higher) which is created in Mode2 (this is very important) and burn it on the lowest speed (1x-2x), as well dowload and burn KeyCD (all links you can find on this forum)
2. Swith off the ignition, disconnect navi device (from the behind) for 15-20 min, connect again.
3. Insert the disk from step 1 into navi and wait for starting the upgrade process (it could take several minutes till this process comes, be patient)
4. After finishing the update process if your navi will ask to insert KeyCD, insert it
Lood luck, hope this will help you....

Regarding the sound - check the radiomodule ,looks like it dead... Does the red led on the boardmonitor is flashing?