diff --git a/services/discord-gateway/src/modules/voice-recording/voiceTranscriber.ts b/services/discord-gateway/src/modules/voice-recording/voiceTranscriber.ts
index 433f7fd2..5d058538 100644
--- a/services/discord-gateway/src/modules/voice-recording/voiceTranscriber.ts
+++ b/services/discord-gateway/src/modules/voice-recording/voiceTranscriber.ts
@@ -30,12 +30,16 @@ export async function transcribeRecording(
 
     const response = await openai.audio.transcriptions.create({
       file: createReadStream(oggPath),
-      model: "whisper-1",
+      model: config.AI_VOICE_TRANSCRIPTION_MODEL,
       // No `language` param → Whisper auto-detects (handles id/en mixed).
-      response_format: "text",
+      // `json` (not `text`): 9router/omniroute proxies only json/verbose_json
+      // transcription responses; `text` returns 400 through the router.
+      response_format: "json",
     });
 
-    const text = typeof response === "string" ? response.trim() : null;
+    // With response_format "json", the SDK returns an object with `text`.
+    const text =
+      (typeof response === "string" ? response : response.text)?.trim() || null;
     if (!text) {
       logger.warn({ oggPath }, "Empty transcription result");
       return null;
diff --git a/services/discord-gateway/src/shared/config/index.ts b/services/discord-gateway/src/shared/config/index.ts
index 0e92e357..74eac44f 100644
--- a/services/discord-gateway/src/shared/config/index.ts
+++ b/services/discord-gateway/src/shared/config/index.ts
@@ -340,6 +340,11 @@ export const configSchema = z
       .optional()
       .transform((v) => v === "true")
       .default(false),
+    // Whisper model routed through the LLM base URL. Through 9router/omniroute
+    // use a provider-qualified id that has credentials (e.g.
+    // openrouter/openai/whisper-1) — bare `whisper-1` maps to the `openai`
+    // provider which the router rejects with "No credentials for provider".
+    AI_VOICE_TRANSCRIPTION_MODEL: z.string().default("whisper-1"),
 
     // ── Auto Delete ─────────────────────────────────────────────────────
     AUTO_DELETE_FLAGGED_ENABLED: z