diff --git a/README.md b/README.md
index eb2836d..fe7a7be 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,7 @@ The package can be installed by adding `membrane_aac_fdk_plugin` to your list of
 ```elixir
 def deps do
   [
-    {:membrane_aac_fdk_plugin, "~> 0.18.7"}
+    {:membrane_aac_fdk_plugin, "~> 0.18.8"}
   ]
 end
 ```
diff --git a/lib/membrane_aac_fdk_plugin/encoder.ex b/lib/membrane_aac_fdk_plugin/encoder.ex
index eb15346..bb9c8ae 100644
--- a/lib/membrane_aac_fdk_plugin/encoder.ex
+++ b/lib/membrane_aac_fdk_plugin/encoder.ex
@@ -277,7 +277,8 @@ defmodule Membrane.AAC.FDK.Encoder do
   end
 
   defp validate_pts_integrity(packets, input_pts) do
-    with [%Buffer{pts: first_pts}, %Buffer{pts: second_pts} | _tail] <- packets do
+    with [%Buffer{pts: first_pts}, %Buffer{pts: second_pts} | _tail]
+         when first_pts != nil and second_pts != nil <- packets do
       duration = second_pts - first_pts
       epsilon = duration / 10
 
diff --git a/mix.exs b/mix.exs
index 5308a8b..45696cb 100644
--- a/mix.exs
+++ b/mix.exs
@@ -1,7 +1,7 @@
 defmodule Membrane.AAC.FDK.Plugin.MixProject do
   use Mix.Project
 
-  @version "0.18.7"
+  @version "0.18.8"
   @github_url "https://github.com/membraneframework/membrane_aac_fdk_plugin"
 
   def project do
diff --git a/test/membrane_element_fdk_aac/pts_test.exs b/test/membrane_element_fdk_aac/pts_test.exs
new file mode 100644
index 0000000..30664b0
--- /dev/null
+++ b/test/membrane_element_fdk_aac/pts_test.exs
@@ -0,0 +1,77 @@
+defmodule Membrane.FLAC.Parser.IntegrationTest do
+  use ExUnit.Case, async: true
+  import Membrane.Testing.Assertions
+  alias Membrane.{Pipeline, Time}
+
+  test "encode with timestamps" do
+    pipeline = prepare_pts_test_pipeline(true)
+
+    Enum.each(0..294, fn index ->
+      assert_sink_buffer(pipeline, :sink, %Membrane.Buffer{pts: out_pts})
+
+      # every other buffer gets queued and concated with next one to be big enough, because of that we expect different pts than on input
+      assert out_pts == (index * 2 * 1000) |> Time.nanoseconds()
+    end)
+
+    Pipeline.terminate(pipeline)
+  end
+
+  test "encode without timestamps" do
+    pipeline = prepare_pts_test_pipeline(false)
+
+    Enum.each(0..294, fn _index ->
+      assert_sink_buffer(pipeline, :sink, %Membrane.Buffer{pts: out_pts})
+      assert out_pts == nil
+    end)
+
+    Pipeline.terminate(pipeline)
+  end
+
+  defp prepare_pts_test_pipeline(with_pts?) do
+    import Membrane.ChildrenSpec
+
+    spec =
+      child(:source, %Membrane.Testing.Source{
+        output: buffers_from_file(with_pts?),
+        stream_format: %Membrane.RawAudio{
+          sample_format: :s16le,
+          sample_rate: 16_000,
+          channels: 1
+        }
+      })
+      |> child(:aac_encoder, Membrane.AAC.FDK.Encoder)
+      |> child(:sink, Membrane.Testing.Sink)
+
+    Membrane.Testing.Pipeline.start_link_supervised!(spec: spec)
+  end
+
+  defp buffers_from_file(with_pts?) do
+    # 589 buffers is generated from this binary
+    binary = "../fixtures/input-encoder.raw" |> Path.expand(__DIR__) |> File.read!()
+
+    split_binary(binary)
+    |> Enum.with_index()
+    |> Enum.map(fn {payload, index} ->
+      %Membrane.Buffer{
+        payload: payload,
+        pts:
+          if with_pts? do
+            (index * 1000) |> Time.nanoseconds()
+          else
+            nil
+          end
+      }
+    end)
+  end
+
+  @spec split_binary(binary(), list(binary())) :: list(binary())
+  def split_binary(binary, acc \\ [])
+
+  def split_binary(<<binary::binary-size(1024), rest::binary>>, acc) do
+    split_binary(rest, [binary] ++ acc)
+  end
+
+  def split_binary(rest, acc) when byte_size(rest) <= 1024 do
+    Enum.reverse(acc) ++ [rest]
+  end
+end