diff --git a/libraries/dsp/filter/tb/vhdl/tb_fil_ppf_single.vhd b/libraries/dsp/filter/tb/vhdl/tb_fil_ppf_single.vhd
index c0304fe5fb76184b61119d3d6a68524683def62f..b8e1048f52a11f72879ec955636a1d5818710f05 100644
--- a/libraries/dsp/filter/tb/vhdl/tb_fil_ppf_single.vhd
+++ b/libraries/dsp/filter/tb/vhdl/tb_fil_ppf_single.vhd
@@ -74,7 +74,7 @@ entity tb_fil_ppf_single is
       --   coef_dat_w     : natural; -- = 16, data width of the FIR coefficients
       -- end record;
     g_file_index_arr    : t_nat_natural_arr := array_init(0, 128, 1); 
-    g_coefs_file_prefix : string            := "../../data/coef"      
+    g_coefs_file_prefix : string            := "hex/coef"      
   );
 end entity tb_fil_ppf_single;
 
@@ -131,12 +131,18 @@ begin
       in_val <= '1';                      
       proc_common_wait_some_cycles(clk, 1);
     END LOOP;
+    
+    in_val <= '0';
+    proc_common_wait_some_cycles(clk, 32);
+    
     FOR J IN 0 TO g_fil_ppf.nof_taps-2 + 2 LOOP                                                
       FOR I IN 0 TO g_fil_ppf.nof_bands-1 LOOP        
         in_dat <= (OTHERS => '0'); 
         in_val <= '1';
         proc_common_wait_some_cycles(clk, 1);
       END LOOP;
+      in_val <= '0';
+      proc_common_wait_some_cycles(clk, 32);
     END LOOP;                            
     in_dat <= (OTHERS => '0'); 
     in_val <= '0';