I have the same problem with my Unidens BCD436HP & BCD536HP both loaded with the Full National Database. On march 1rst about 02:00 the scanner went silent and have not been able to receive much of anything and no trunking reception. The scanners scan, but do not stop on most anything. The 436 (handheld) was turned off, not plugged in and the 536 (Base/ Mobile) was plugged in running 24/7.
I have been researching and looking for a fix including updating the firmware, reloading the database and upgrading my subscription on RR but no luck yet. I'm thinking the Splinter offset somehow got changed and I'm looking into that aspect now.
Any help would be greatly appreciated, this is driving me nuts!