diff --git a/spec/apex/encoder/aprs_kiss_spec.rb b/spec/apex/encoder/aprs_kiss_spec.rb
index 16ba887b0d99efca81a208e89a234304d60ca6de..5333f47c40e82db757b9a739a63f7b308f4e4bdf 100644
--- a/spec/apex/encoder/aprs_kiss_spec.rb
+++ b/spec/apex/encoder/aprs_kiss_spec.rb
@@ -17,7 +17,7 @@ FRAME_MAP = {
 
 describe Apex::AprsKiss do
 
-  let(:data_stream) { double("data_stream") }
+  let(:data_stream) { double(Kiss::KissAbstract, kind_of?: true) }
   let(:aprs_kiss) { Apex::AprsKiss.new(data_stream) }
 
   describe ".read" do