diff --git a/accounts/keystore/account_cache_test.go b/accounts/keystore/account_cache_test.go
index e3dc31065..fe9233c04 100644
--- a/accounts/keystore/account_cache_test.go
+++ b/accounts/keystore/account_cache_test.go
@@ -59,7 +59,7 @@ func TestWatchNewFile(t *testing.T) {
 
 	// Ensure the watcher is started before adding any files.
 	ks.Accounts()
-	time.Sleep(200 * time.Millisecond)
+	time.Sleep(1000 * time.Millisecond)
 
 	// Move in the files.
 	wantAccounts := make([]accounts.Account, len(cachetestAccounts))
@@ -349,6 +349,9 @@ func TestUpdatedKeyfileContents(t *testing.T) {
 		return
 	}
 
+	// needed so that modTime of `file` is different to its current value after forceCopyFile
+	time.Sleep(1000 * time.Millisecond)
+
 	// Now replace file contents
 	if err := forceCopyFile(file, cachetestAccounts[1].URL.Path); err != nil {
 		t.Fatal(err)
@@ -362,6 +365,9 @@ func TestUpdatedKeyfileContents(t *testing.T) {
 		return
 	}
 
+	// needed so that modTime of `file` is different to its current value after forceCopyFile
+	time.Sleep(1000 * time.Millisecond)
+
 	// Now replace file contents again
 	if err := forceCopyFile(file, cachetestAccounts[2].URL.Path); err != nil {
 		t.Fatal(err)
@@ -374,6 +380,10 @@ func TestUpdatedKeyfileContents(t *testing.T) {
 		t.Error(err)
 		return
 	}
+
+	// needed so that modTime of `file` is different to its current value after ioutil.WriteFile
+	time.Sleep(1000 * time.Millisecond)
+
 	// Now replace file contents with crap
 	if err := ioutil.WriteFile(file, []byte("foo"), 0644); err != nil {
 		t.Fatal(err)