diff --git a/src/compat/can_rely_on_request_media_key_system_access.ts b/src/compat/can_rely_on_request_media_key_system_access.ts
index 4270923af7d..9eff3395cf2 100644
--- a/src/compat/can_rely_on_request_media_key_system_access.ts
+++ b/src/compat/can_rely_on_request_media_key_system_access.ts
@@ -40,3 +40,10 @@ export function canRelyOnRequestMediaKeySystemAccess(keySystem: string): boolean
   }
   return true;
 }
+/**
+ * The PlayReadyHeader sample that will be used to test if the CDM is supported.
+ * The KID does not matter because no content will be played, it's only to check if
+ * the CDM is capable of creating a session and generating a request.
+ */
+export const PLAY_READY_HEADER_EXAMPLE =
+  '<WRMHEADER xmlns="http://schemas.microsoft.com/DRM/2007/03/PlayReadyHeader" version="4.0.0.0"><DATA><PROTECTINFO><KEYLEN>16</KEYLEN><ALGID>AESCTR</ALGID></PROTECTINFO><KID>ckB07BNLskeUq0qd83fTbA==</KID><DS_ID>yYIPDBca1kmMfL60IsfgAQ==</DS_ID><CUSTOMATTRIBUTES xmlns=""><encryptionref>312_4024_2018127108</encryptionref></CUSTOMATTRIBUTES><CHECKSUM>U/tsUYRgMzw=</CHECKSUM></DATA></WRMHEADER>';
diff --git a/src/main_thread/decrypt/find_key_system.ts b/src/main_thread/decrypt/find_key_system.ts
index 3b74e187015..dee20545ec7 100644
--- a/src/main_thread/decrypt/find_key_system.ts
+++ b/src/main_thread/decrypt/find_key_system.ts
@@ -14,7 +14,10 @@
  * limitations under the License.
  */
 
-import { canRelyOnRequestMediaKeySystemAccess } from "../../compat/can_rely_on_request_media_key_system_access";
+import {
+  canRelyOnRequestMediaKeySystemAccess,
+  PLAY_READY_HEADER_EXAMPLE,
+} from "../../compat/can_rely_on_request_media_key_system_access";
 import type { ICustomMediaKeySystemAccess } from "../../compat/eme";
 import eme from "../../compat/eme";
 import shouldRenewMediaKeySystemAccess from "../../compat/should_renew_media_key_system_access";
@@ -378,7 +381,7 @@ export default function getMediaKeySystemAccess(
     );
 
     try {
-      const keySystemAccess = await testOneKeySystem(keyType, keySystemConfigurations);
+      const keySystemAccess = await testKeySystem(keyType, keySystemConfigurations);
       log.info("DRM: Found compatible keysystem", keyType, index + 1);
       return {
         type: "create-media-key-system-access" as const,
@@ -403,7 +406,7 @@ export default function getMediaKeySystemAccess(
  * @param {Array.<MediaKeySystemMediaCapability>} keySystemConfigurations - Configurations for this keySystem
  * @returns Promise resolving with the MediaKeySystemAccess. Rejects if unsupported.
  */
-export async function testOneKeySystem(
+export async function testKeySystem(
   keyType: string,
   keySystemConfigurations: MediaKeySystemConfiguration[],
 ) {
@@ -416,10 +419,7 @@ export async function testOneKeySystem(
     try {
       const mediaKeys = await keySystemAccess.createMediaKeys();
       const session = mediaKeys.createSession();
-      // this is just and an example initData to test if the CDM is capable of generating a request
-      const playReadyHeader =
-        '<WRMHEADER xmlns="http://schemas.microsoft.com/DRM/2007/03/PlayReadyHeader" version="4.0.0.0"><DATA><PROTECTINFO><KEYLEN>16</KEYLEN><ALGID>AESCTR</ALGID></PROTECTINFO><KID>ckB07BNLskeUq0qd83fTbA==</KID><LA_URL>http://drm.canal-plus.com/</LA_URL><LUI_URL>http://drm.canal-plus.com/</LUI_URL><DS_ID>yYIPDBca1kmMfL60IsfgAQ==</DS_ID><CUSTOMATTRIBUTES xmlns=""><encryptionref>312_4024_2018127108</encryptionref></CUSTOMATTRIBUTES><CHECKSUM>U/tsUYRgMzw=</CHECKSUM></DATA></WRMHEADER>';
-      const initData = generatePlayReadyInitData(playReadyHeader);
+      const initData = generatePlayReadyInitData(PLAY_READY_HEADER_EXAMPLE);
       await session.generateRequest("cenc", initData);
     } catch (err) {
       log.debug("DRM: KeySystemAccess was granted but it is not usable");
diff --git a/src/utils/__tests__/generate_init_data.test.ts b/src/utils/__tests__/generate_init_data.test.ts
index 62eb5f624bf..42ab6a4e8ee 100644
--- a/src/utils/__tests__/generate_init_data.test.ts
+++ b/src/utils/__tests__/generate_init_data.test.ts
@@ -3,14 +3,14 @@ import { utf16LEToStr } from "../string_parsing";
 
 describe("utils - generatePlayReadyInitData", () => {
   const playReadyHeader =
-    '<WRMHEADER xmlns="http://schemas.microsoft.com/DRM/2007/03/PlayReadyHeader" version="4.0.0.0"><DATA><PROTECTINFO><KEYLEN>16</KEYLEN><ALGID>AESCTR</ALGID></PROTECTINFO><KID>ckB07BNLskeUq0qd83fTbA==</KID><LA_URL>http://drm.canal-plus.com/</LA_URL><LUI_URL>http://drm.canal-plus.com/</LUI_URL><DS_ID>yYIPDBca1kmMfL60IsfgAQ==</DS_ID><CUSTOMATTRIBUTES xmlns=""><encryptionref>312_4024_2018127108</encryptionref></CUSTOMATTRIBUTES><CHECKSUM>U/tsUYRgMzw=</CHECKSUM></DATA></WRMHEADER>';
+    '<WRMHEADER xmlns="http://schemas.microsoft.com/DRM/2007/03/PlayReadyHeader" version="4.0.0.0"><DATA><PROTECTINFO><KEYLEN>16</KEYLEN><ALGID>AESCTR</ALGID></PROTECTINFO><KID>ckB07BNLskeUq0qd83fTbA==</KID><DS_ID>yYIPDBca1kmMfL60IsfgAQ==</DS_ID><CUSTOMATTRIBUTES xmlns=""><encryptionref>312_4024_2018127108</encryptionref></CUSTOMATTRIBUTES></DATA></WRMHEADER>';
 
   const initData = generatePlayReadyInitData(playReadyHeader);
   const decodedInitDataUtf16LE = utf16LEToStr(initData);
 
   it("has correct length", () => {
     // the expected length for an initData with that PlayReady header.
-    expect(initData.length).toBe(996);
+    expect(initData.length).toBe(754);
   });
 
   it("has the playerReadyHeader in it", () => {