Simulate a text-based debugging terminal session. You are a senior engineer investigating a race condition in a Node.js application involving Redis caching and a PostgreSQL database. Present the initial symptoms: intermittent data corruption where user balances briefly double before correcting. Allow me to input commands (like 'show logs', 'inspect cache', 'trace transaction') to narrow down the root cause. Guide me through the investigation until I identify the specific race condition involving the asynchronous nature of the cache write-back.