diff --git a/src/main/bootstrap/process-guards.ts b/src/main/bootstrap/process-guards.ts
index ff24df3..d97a5f0 100644
--- a/src/main/bootstrap/process-guards.ts
+++ b/src/main/bootstrap/process-guards.ts
@@ -3,9 +3,9 @@ import logger from '../services/logger/index'
 import { logAudit, closeAuditLogger } from '../services/logger/audit-logger'
 
 export function setupProcessGuards(): void {
-  process.on('uncaughtException', async (err) => {
+  process.on('uncaughtException', (err) => {
     logger.error('Uncaught exception', { error: err })
-    await logAudit('SYSTEM_CRASH', 'system', {
+    logAudit('SYSTEM_CRASH', 'system', {
       username: 'system',
       computerName: process.env.COMPUTERNAME || 'unknown',
       resource: 'main-process',
@@ -15,9 +15,9 @@ export function setupProcessGuards(): void {
     setTimeout(() => process.exit(1), 1000)
   })
 
-  process.on('unhandledRejection', async (reason) => {
+  process.on('unhandledRejection', (reason) => {
     logger.error('Unhandled Rejection', { reason: String(reason) })
-    await logAudit('SYSTEM_ERROR', 'system', {
+    logAudit('SYSTEM_ERROR', 'system', {
       username: 'system',
       computerName: process.env.COMPUTERNAME || 'unknown',
       resource: 'main-process',
diff --git a/src/main/ipc/extractor-handler.ts b/src/main/ipc/extractor-handler.ts
index 4b885c5..d1b093d 100644
--- a/src/main/ipc/extractor-handler.ts
+++ b/src/main/ipc/extractor-handler.ts
@@ -292,7 +292,7 @@ export function registerExtractorHandlers(): void {
                 recordCount: result.recordCount,
                 errorCount: result.errors.length
               }
-            }).catch((err) => log.warn('Failed to write audit log', { err }))
+            })
           }
 
           return result
diff --git a/src/main/ipc/logger-handler.ts b/src/main/ipc/logger-handler.ts
index 74f3b74..e3c4474 100644
--- a/src/main/ipc/logger-handler.ts
+++ b/src/main/ipc/logger-handler.ts
@@ -9,7 +9,7 @@
  * - Error-level logs bypass circuit breaker
  */
 
-import { ipcMain, BrowserWindow } from 'electron'
+import { ipcMain } from 'electron'
 import winston from 'winston'
 import { createLogger } from '../services/logger'
 import logger from '../services/logger'
diff --git a/src/main/ipc/settings-handler.ts b/src/main/ipc/settings-handler.ts
index 9e3377a..747d2bb 100644
--- a/src/main/ipc/settings-handler.ts
+++ b/src/main/ipc/settings-handler.ts
@@ -74,7 +74,7 @@ export function registerSettingsHandlers(): void {
             resource: 'ERP_CONFIG',
             status: 'success',
             metadata: { changeType: 'erp_credentials', usernameChanged: !!settings.erp.username }
-          }).catch((err) => log.warn('Failed to write audit log', { err }))
+          })
         }
 
         return { success: true }
diff --git a/src/main/services/auth/auth-application-service.ts b/src/main/services/auth/auth-application-service.ts
index 209701a..46c3d2b 100644
--- a/src/main/services/auth/auth-application-service.ts
+++ b/src/main/services/auth/auth-application-service.ts
@@ -176,8 +176,6 @@ export class AuthApplicationService {
     actorId: string,
     payload: Parameters<typeof logAudit>[2]
   ): void {
-    logAudit(action, actorId, payload).catch((err) =>
-      log.warn('Failed to write audit log', { err })
-    )
+    logAudit(action, actorId, payload)
   }
 }
diff --git a/src/main/services/cleaner/cleaner-application-service.ts b/src/main/services/cleaner/cleaner-application-service.ts
index 0feeea0..96fce84 100644
--- a/src/main/services/cleaner/cleaner-application-service.ts
+++ b/src/main/services/cleaner/cleaner-application-service.ts
@@ -274,7 +274,7 @@ export class CleanerApplicationService {
           ? 'failure'
           : 'success'
 
-    await logAudit('CLEAN', String(currentUser.id), {
+    logAudit('CLEAN', String(currentUser.id), {
       username: currentUser.username,
       computerName: (await import('os')).hostname(),
       resource: 'MATERIAL_PLAN',
@@ -288,7 +288,7 @@ export class CleanerApplicationService {
         materialsSkipped: result.materialsSkipped,
         errorCount: result.errors.length
       }
-    }).catch((err) => log.warn('Failed to write audit log', { err }))
+    })
   }
 
   private async generateAndUploadReport(
diff --git a/src/main/services/logger/audit-logger.ts b/src/main/services/logger/audit-logger.ts
index 4ad39a7..9500af1 100644
--- a/src/main/services/logger/audit-logger.ts
+++ b/src/main/services/logger/audit-logger.ts
@@ -46,7 +46,7 @@ const jsonlFormat = winston.format.printf(({ message }) => {
  */
 const auditLogger = winston.createLogger({
   level: 'info',
-  silent: false,
+  silent: true,
   transports: []
 })
 
@@ -57,6 +57,9 @@ const auditLogger = winston.createLogger({
  * @param retentionDays - Number of days to retain audit logs
  */
 export function applyAuditConfig(retentionDays: number): void {
+  // Enable logging now that config is loaded
+  auditLogger.silent = false
+
   // Remove existing DailyRotateFile transports
   const existingTransports = auditLogger.transports.filter((t) => t instanceof DailyRotateFile)
   for (const transport of existingTransports) {
@@ -83,9 +86,8 @@ export function applyAuditConfig(retentionDays: number): void {
  * @param action - The action that was performed
  * @param userId - User ID who performed the action
  * @param details - Additional details including username, computerName, resource, status, and optional metadata
- * @returns Promise that resolves when the log is written (non-blocking)
  */
-export async function logAudit(
+export function logAudit(
   action: string,
   userId: string,
   details: {
@@ -95,7 +97,7 @@ export async function logAudit(
     status: 'success' | 'failure' | 'partial'
     metadata?: Record<string, unknown>
   }
-): Promise<void> {
+): void {
   const entry: AuditEntry = {
     timestamp: new Date().toISOString(),
     action,
@@ -115,8 +117,7 @@ export async function logAudit(
 /**
  * Flush and close the audit logger (call on app shutdown)
  */
-export async function closeAuditLogger(): Promise<void> {
-  // Winston logger.close() is synchronous
+export function closeAuditLogger(): void {
   auditLogger.close()
 }
 
diff --git a/src/main/services/logger/index.ts b/src/main/services/logger/index.ts
index 49e115d..c6ae1ba 100644
--- a/src/main/services/logger/index.ts
+++ b/src/main/services/logger/index.ts
@@ -56,7 +56,21 @@ const consoleFormat = winston.format.combine(
       }
     }
 
-    const metaStr = Object.keys(meta).length > 0 ? ` ${JSON.stringify(meta, null, 2)}` : ''
+    let metaStr = ''
+    if (Object.keys(meta).length > 0) {
+      try {
+        metaStr = ` ${JSON.stringify(meta, null, 2)}`
+      } catch {
+        // Fallback for circular references: stringify primitives, replace objects with placeholder
+        metaStr = ` ${JSON.stringify(
+          Object.fromEntries(
+            Object.entries(meta).map(([k, v]) => [k, typeof v === 'object' ? '[Object]' : v])
+          ),
+          null,
+          2
+        )}`
+      }
+    }
     return `${timestamp} [${level}]${contextStr} ${message}${errorStr}${metaStr}`
   })
 )
@@ -77,9 +91,7 @@ const fileFormat = winston.format.combine(
     // Serialize any error in meta fields (skip if already serialized)
     for (const key of Object.keys(info)) {
       if (key !== 'error' && info[key] instanceof Error) {
-        info[key] = IS_PROD
-          ? sanitizeError(serializeError(info[key]))
-          : serializeError(info[key])
+        info[key] = IS_PROD ? sanitizeError(serializeError(info[key])) : serializeError(info[key])
       }
     }
 
diff --git a/src/main/services/logger/shared.ts b/src/main/services/logger/shared.ts
index 989b5b0..e319bb4 100644
--- a/src/main/services/logger/shared.ts
+++ b/src/main/services/logger/shared.ts
@@ -16,6 +16,8 @@ export function getLogDir(): string {
     return app.getPath('logs')
   }
   // Fallback for development or before app is ready
+  // Note: synchronous FS calls are acceptable here because this branch only
+  // executes in dev environments when app is not yet ready (rare, at startup).
   const devLogDir = path.join(process.cwd(), 'logs')
   if (!fs.existsSync(devLogDir)) {
     fs.mkdirSync(devLogDir, { recursive: true })
diff --git a/tests/unit/audit-logger.test.ts b/tests/unit/audit-logger.test.ts
index b62f80a..f070d94 100644
--- a/tests/unit/audit-logger.test.ts
+++ b/tests/unit/audit-logger.test.ts
@@ -204,8 +204,8 @@ describe('Audit Logger - Real File Integration', () => {
   it('should close audit logger without errors', async () => {
     const { closeAuditLogger } = await import('../../src/main/services/logger/audit-logger')
 
-    // Should resolve without throwing
-    await expect(closeAuditLogger()).resolves.toBeUndefined()
+    // Should complete without throwing
+    expect(() => closeAuditLogger()).not.toThrow()
   })
 
   it('should handle special characters in fields', async () => {