diff --git a/tests/integration/chatcore-compression-integration.test.ts b/tests/integration/chatcore-compression-integration.test.ts
index fd5038e711..cb0ac06cec 100644
--- a/tests/integration/chatcore-compression-integration.test.ts
+++ b/tests/integration/chatcore-compression-integration.test.ts
@@ -611,10 +611,12 @@ test("chatCore integration: assigned compression combo applies language packs an
       autoClarity: true,
     },
     languageConfig: {
-      enabled: false,
-      defaultLanguage: "en",
-      autoDetect: true,
-      enabledPacks: ["en"],
+      enabled: true,
+      // autoDetect would read the (English) user turn and resolve back to "en",
+      // so the pack under test has to be pinned explicitly.
+      autoDetect: false,
+      defaultLanguage: "pt-BR",
+      enabledPacks: ["pt-BR"],
     },
   });
 
@@ -719,10 +721,12 @@ test("chatCore integration: default stacked compression combo applies for unassi
       autoClarity: true,
     },
     languageConfig: {
-      enabled: false,
-      defaultLanguage: "en",
-      autoDetect: true,
-      enabledPacks: ["en"],
+      enabled: true,
+      // autoDetect would read the (English) user turn and resolve back to "en",
+      // so the pack under test has to be pinned explicitly.
+      autoDetect: false,
+      defaultLanguage: "pt-BR",
+      enabledPacks: ["pt-BR"],
     },
   });