         }
 
         let speechToText = SpeechToText(username: "invalid", password: "invalid")
-        let settings = RecognitionSettings(contentType: .wav)
+        let settings = RecognitionSettings(contentType: "audio/wav")
         let failure = { (error: Error) in
             if error.localizedDescription.contains("Please confirm that your credentials match") {
                 expectation.fulfill()

            }

            switch customizationStatus {
            case .available, .ready:
                break // do nothing, because the customization is trained
            case .pending: // train -> then fail (wait for training)
                print("Training the `trained customization` used for tests.")
                self.trainCustomizationWithCorpus()
                print("The customization has been trained and is ready for use.")
            case .training: // fail (wait for training)
                let message = "Please wait a few minutes for the trained customization to finish " +
                "training. You can try running the tests again afterwards."
                XCTFail(message)
                return
            case .failed: // training failed => delete & retry
                let message = "Creating a trained ranker has failed. Check the errors " +
                "within the corpus and customization and retry."
                XCTFail(message)

            let description2 = "Wait until the corpus is processed before deleting it."
            let expectation2 = self.expectation(description: description2)

            speechToText.getCorpus(customizationID: self.trainedCustomizationID, corpusName: newCorpusName, failure: failWithError) {
                corpus in
                if corpus.status == "analyzed" {
                    processed = true
                } else if corpus.status == "undetermined" {
                    let message = "There was an error when processing the corpus, please check " +
                    "and fix the errors before trying again."
                    XCTFail(message)
                }
                expectation2.fulfill()
            }
            waitForExpectations()

