A bit of a confusing one this.
We have a database (A) that has multiple replication jobs on (local publication)
For some reason one job fails intermitently when starting the snapshot agent (I can see this in the job history).
The errror indicated the snapshot agent can't logon to a database (B) because its in single use mode (error 924)
Only problem is that this database (B) has nothing to do with the replication job on database (A)!