Is this running as an embedded engine or a standalone server? One thing about Firebird is that since it is embeddable, in that mode other application bugs could corrupt the database. In the other case, I would expect you may want to run hardware diagnostics to rule out hardware problems going forward. If you find hardware problems fix them first, then look further.
I'm running the standalone server (Super Classic version) on an EC2 instance. My software is on another machine in the same VPC.