diff --git a/tests/Providers/AbstractProviderTest.php b/tests/Providers/AbstractProviderTest.php
index b15f65f..03e0c7e 100644
--- a/tests/Providers/AbstractProviderTest.php
+++ b/tests/Providers/AbstractProviderTest.php
@@ -4,6 +4,7 @@
 
 use duncan3dc\Speaker\Exceptions\ProviderException;
 use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Psr7\Utils;
 use Mockery;
 use Mockery\MockInterface;
 use PHPUnit\Framework\TestCase;
@@ -55,7 +56,7 @@ public function testSendRequest(): void
     {
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
diff --git a/tests/Providers/AcapelaProviderTest.php b/tests/Providers/AcapelaProviderTest.php
index af1af4c..de90396 100644
--- a/tests/Providers/AcapelaProviderTest.php
+++ b/tests/Providers/AcapelaProviderTest.php
@@ -5,6 +5,7 @@
 use duncan3dc\Speaker\Exceptions\InvalidArgumentException;
 use duncan3dc\Speaker\Providers\AcapelaProvider;
 use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Psr7\Utils;
 use Mockery;
 use Mockery\MockInterface;
 use PHPUnit\Framework\TestCase;
@@ -37,7 +38,7 @@ public function testTextToSpeech(): void
     {
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
@@ -58,7 +59,7 @@ public function testWithVoice(): void
 
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
@@ -87,7 +88,7 @@ public function testWithSpeed(): void
 
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
diff --git a/tests/Providers/GoogleProviderTest.php b/tests/Providers/GoogleProviderTest.php
index 3e70cdb..b4a4d0b 100644
--- a/tests/Providers/GoogleProviderTest.php
+++ b/tests/Providers/GoogleProviderTest.php
@@ -5,6 +5,7 @@
 use duncan3dc\Speaker\Exceptions\InvalidArgumentException;
 use duncan3dc\Speaker\Providers\GoogleProvider;
 use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Psr7\Utils;
 use Mockery;
 use Mockery\MockInterface;
 use PHPUnit\Framework\TestCase;
@@ -37,7 +38,7 @@ public function testTextToSpeech(): void
     {
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
@@ -58,7 +59,7 @@ public function testWithLanguage(): void
 
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
diff --git a/tests/Providers/ResponsiveVoiceProviderTest.php b/tests/Providers/ResponsiveVoiceProviderTest.php
index 041511a..8e629e6 100644
--- a/tests/Providers/ResponsiveVoiceProviderTest.php
+++ b/tests/Providers/ResponsiveVoiceProviderTest.php
@@ -5,6 +5,7 @@
 use duncan3dc\Speaker\Exceptions\InvalidArgumentException;
 use duncan3dc\Speaker\Providers\ResponsiveVoiceProvider;
 use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Psr7\Utils;
 use Mockery;
 use Mockery\MockInterface;
 use PHPUnit\Framework\TestCase;
@@ -37,7 +38,7 @@ public function testTextToSpeech(): void
     {
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
diff --git a/tests/Providers/VoiceRssProviderTest.php b/tests/Providers/VoiceRssProviderTest.php
index 6e763fa..01de5f7 100644
--- a/tests/Providers/VoiceRssProviderTest.php
+++ b/tests/Providers/VoiceRssProviderTest.php
@@ -6,6 +6,7 @@
 use duncan3dc\Speaker\Exceptions\ProviderException;
 use duncan3dc\Speaker\Providers\VoiceRssProvider;
 use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Psr7\Utils;
 use Mockery;
 use Mockery\MockInterface;
 use PHPUnit\Framework\TestCase;
@@ -38,7 +39,7 @@ public function testTextToSpeech(): void
     {
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
@@ -53,7 +54,7 @@ public function testTextToSpeechFailure(): void
     {
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("ERROR: Test Message");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("ERROR: Test Message"));
 
         $this->client->shouldReceive("request")
             ->once()
@@ -76,7 +77,7 @@ public function testWithLanguage(): void
 
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()
@@ -105,7 +106,7 @@ public function testWithSpeed(): void
 
         $response = Mockery::mock(ResponseInterface::class);
         $response->shouldReceive("getStatusCode")->once()->andReturn("200");
-        $response->shouldReceive("getBody")->once()->andReturn("mp3");
+        $response->shouldReceive("getBody")->once()->andReturn(Utils::streamFor("mp3"));
 
         $this->client->shouldReceive("request")
             ->once()