Jobs within the same vault are queued and then run when resources are available. However, if multiple profiles from different vaults run simultaneously and use the same offsite volume pool for duplication, those jobs could all pick the same target media. This would circumvent the queuing mechanism and cause undesirable results. (For example, it could cause a deadlock condition when multiple jobs try to use the same drive at the same time).

Therefore, you should configure Vault so that every vault has its own offsite volume pool.