diff --git a/content/media/test/test_bug495300.html b/content/media/test/test_bug495300.html
index 67995ec2d3a1..f5cd3e3e2910 100644
--- a/content/media/test/test_bug495300.html
+++ b/content/media/test/test_bug495300.html
@@ -17,7 +17,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=495300
 
 if (!navigator.platform.startsWith("Mac")) {
   // not Mac
-  SimpleTest.expectAssertions(0, 1);
+  SimpleTest.expectAssertions(0, 2);
 }
 
 var manager = new MediaTestManager;
diff --git a/toolkit/content/tests/chrome/test_bug557987.xul b/toolkit/content/tests/chrome/test_bug557987.xul
index 5fcf09a0e419..419f056ec1a6 100644
--- a/toolkit/content/tests/chrome/test_bug557987.xul
+++ b/toolkit/content/tests/chrome/test_bug557987.xul
@@ -22,7 +22,7 @@
 <script type="application/javascript">
 <![CDATA[
 
-if (navigator.platform.startsWith("Mac")) {
+if (!navigator.platform.startsWith("Linux")) {
   SimpleTest.expectAssertions(0, 5);
 }