DVR firmware for the AHB8004T-NB model on board N68C, version V1.01B, compressed with 7-Zip to 14.5 MB. The name points to a four-channel hybrid recorder, but it does not say which brand. Extract it with 7-Zip and use the image to restore a unit that hangs at startup, either through the upgrade menu or by writing the flash chip directly. Make sure the N68C board marking matches your hardware, and back up the existing flash before programming.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @vinafix_bios. Enginerys does not host this file.
How to open a .7z file
High-ratio compressed archive, often used for large BIOS collections.
7-ZipWinRARKeka (macOS)