diff --git a/library/util_fir_int/util_fir_int.v b/library/util_fir_int/util_fir_int.v
index 44af4643a..79a0b457b 100644
--- a/library/util_fir_int/util_fir_int.v
+++ b/library/util_fir_int/util_fir_int.v
@@ -65,7 +65,7 @@ module util_fir_int (
     end
   end
 
-  assign {channel_1, channel_0} = (interpolate == 1'b1) ? m_axis_data_tdata_s : s_axis_data_tdata;
+  assign {channel_1, channel_0} = (interpolate == 1'b1) ? {m_axis_data_tdata_s[30:16],1'b0,m_axis_data_tdata_s[14:0], 1'b0} : s_axis_data_tdata;
   assign s_axis_data_tready = (interpolate == 1'b1) ? s_axis_data_tready_r : dac_read;
 
   fir_interp interpolator (