diff --git a/ivas_processing_scripts/audiotools/wrappers/reverb.py b/ivas_processing_scripts/audiotools/wrappers/reverb.py
index fc37b0f6ba82746d793f9bfff92447d48f42149b..62c6dfdc8e5eb656f8c80e99738b79ea48dda0a4 100644
--- a/ivas_processing_scripts/audiotools/wrappers/reverb.py
+++ b/ivas_processing_scripts/audiotools/wrappers/reverb.py
@@ -89,6 +89,9 @@ def reverb(
             tmp_input.audio = resample_itu(tmp_input, IR.fs)
             tmp_input.fs = IR.fs
 
+        # add trailing zeros
+        tmp_input.audio = np.concatenate([tmp_input.audio, np.zeros((IR.audio.shape[0]-1, 1))])
+
         # write input audio signal to temporary file in .pcm format
         tmp_input_file = tmp_dir.joinpath("tmp_reverbIn.pcm")
         write(tmp_input_file, tmp_input.audio, tmp_input.fs)
diff --git a/ivas_processing_scripts/generation/process_ambi_items.py b/ivas_processing_scripts/generation/process_ambi_items.py
index 6417684194b1d716edb1908630c9a1267ee2d3b1..cd8b80d39b343585f7948360d85b9ea2fbd11e99 100644
--- a/ivas_processing_scripts/generation/process_ambi_items.py
+++ b/ivas_processing_scripts/generation/process_ambi_items.py
@@ -203,6 +203,7 @@ def generate_ambi_scene(
     else:
         ambi_format = "FOA"
 
+    len_s1 = 0
     y = audio.SceneBasedAudio(ambi_format)
     for i in range(N_sources):
         # parse parameters from the scene description
@@ -233,6 +234,9 @@ def generate_ambi_scene(
             fs=cfg.IR_fs,
         )
 
+        if i == 0:
+            len_s1 = x.audio.shape[0]
+
         # convolve with the FOA/HOA2 IR
         if ambi_format == "FOA":
             x = reverb_foa(x, IR)
@@ -246,7 +250,7 @@ def generate_ambi_scene(
         # shift the second (and all other) source files (positive shift creates overlap, negative shift creates a gap)
         if i > 0:
             # get the length of the first source file
-            N_delay = len(y.audio[:, 0])
+            N_delay = len_s1
 
             # add the shift
             N_delay += int(-source_overlap * x.fs)
diff --git a/ivas_processing_scripts/generation/process_stereo_items.py b/ivas_processing_scripts/generation/process_stereo_items.py
index 4d58eb22f6e956317844d48695c60d57453d36a7..86fdb030bcd5da5b59b2f492ed2ee847f1ef27c0 100644
--- a/ivas_processing_scripts/generation/process_stereo_items.py
+++ b/ivas_processing_scripts/generation/process_stereo_items.py
@@ -193,6 +193,7 @@ def generate_stereo_scene(
     else:
         source_overlap = 0.0
 
+    len_s1 = 0
     y = audio.ChannelBasedAudio("STEREO")
     for i in range(N_sources):
         # parse parameters from the scene description
@@ -223,6 +224,9 @@ def generate_stereo_scene(
             fs=cfg.IR_fs,
         )
 
+        if i == 0:
+            len_s1 = x.audio.shape[0]
+
         # convolve with stereo IR
         x = reverb_stereo(x, IR)
 
@@ -233,7 +237,7 @@ def generate_stereo_scene(
         # shift the second (and all other) source files (positive shift creates overlap, negative shift creates a gap)
         if i > 0:
             # get the length of the first source file
-            N_delay = len(y.audio[:, 0])
+            N_delay = len_s1
 
             # add the shift
             N_delay += int(-source_overlap * x.fs)