diff --git a/pin/pin_test.go b/pin/pin_test.go
index 7bf0756df..1ea302823 100644
--- a/pin/pin_test.go
+++ b/pin/pin_test.go
@@ -12,7 +12,7 @@ import (
 func randNode() (*mdag.Node, util.Key) {
 	nd := new(mdag.Node)
 	nd.Data = make([]byte, 32)
-	util.NewFastRand().Read(nd.Data)
+	util.NewTimeSeededRand().Read(nd.Data)
 	k, _ := nd.Key()
 	return nd, k
 }
diff --git a/unixfs/io/dagmodifier_test.go b/unixfs/io/dagmodifier_test.go
index d45559b3a..edb4d6f76 100644
--- a/unixfs/io/dagmodifier_test.go
+++ b/unixfs/io/dagmodifier_test.go
@@ -28,7 +28,7 @@ func getMockDagServ(t *testing.T) mdag.DAGService {
 func getNode(t *testing.T, dserv mdag.DAGService, size int64) ([]byte, *mdag.Node) {
 	dw := NewDagWriter(dserv, &chunk.SizeSplitter{500})
 
-	n, err := io.CopyN(dw, u.NewFastRand(), size)
+	n, err := io.CopyN(dw, u.NewTimeSeededRand(), size)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -58,7 +58,7 @@ func getNode(t *testing.T, dserv mdag.DAGService, size int64) ([]byte, *mdag.Nod
 
 func testModWrite(t *testing.T, beg, size uint64, orig []byte, dm *DagModifier) []byte {
 	newdata := make([]byte, size)
-	r := u.NewFastRand()
+	r := u.NewTimeSeededRand()
 	r.Read(newdata)
 
 	if size+beg > uint64(len(orig)) {
@@ -160,7 +160,7 @@ func TestMultiWrite(t *testing.T) {
 	}
 
 	data := make([]byte, 4000)
-	u.NewFastRand().Read(data)
+	u.NewTimeSeededRand().Read(data)
 
 	for i := 0; i < len(data); i++ {
 		n, err := dagmod.WriteAt(data[i:i+1], uint64(i))
@@ -201,7 +201,7 @@ func TestMultiWriteCoal(t *testing.T) {
 	}
 
 	data := make([]byte, 4000)
-	u.NewFastRand().Read(data)
+	u.NewTimeSeededRand().Read(data)
 
 	for i := 0; i < len(data); i++ {
 		n, err := dagmod.WriteAt(data[:i+1], 0)
diff --git a/util/util.go b/util/util.go
index 2fd58c000..6bbca63f6 100644
--- a/util/util.go
+++ b/util/util.go
@@ -97,28 +97,21 @@ func (bcr *byteChanReader) Read(b []byte) (int, error) {
 }
 
 type randGen struct {
-	src rand.Source
+	rand.Rand
 }
 
-func NewFastRand() io.Reader {
-	return &randGen{rand.NewSource(time.Now().UnixNano())}
+func NewTimeSeededRand() io.Reader {
+	src := rand.NewSource(time.Now().UnixNano())
+	return &randGen{
+		Rand: *rand.New(src),
+	}
 }
 
 func (r *randGen) Read(p []byte) (n int, err error) {
-	todo := len(p)
-	offset := 0
-	for {
-		val := int64(r.src.Int63())
-		for i := 0; i < 8; i++ {
-			p[offset] = byte(val & 0xff)
-			todo--
-			if todo == 0 {
-				return len(p), nil
-			}
-			offset++
-			val >>= 8
-		}
+	for i := 0; i < len(p); i++ {
+		p[i] = byte(r.Rand.Intn(255))
 	}
+	return len(p), nil
 }
 
 // GetenvBool is the way to check an env var as a boolean
diff --git a/util/util_test.go b/util/util_test.go
index c2bb8f484..fc668ba31 100644
--- a/util/util_test.go
+++ b/util/util_test.go
@@ -31,7 +31,7 @@ func TestKey(t *testing.T) {
 
 func TestByteChanReader(t *testing.T) {
 	data := make([]byte, 1024*1024)
-	r := NewFastRand()
+ r := NewTimeSeededRand()
 	r.Read(data)
 	dch := make(chan []byte, 8)