diff --git a/aiia_audio_processor.py b/aiia_audio_processor.py
index 0ae43cf..3478c3f 100644
--- a/aiia_audio_processor.py
+++ b/aiia_audio_processor.py
@@ -155,9 +155,9 @@ class AIIA_Audio_PostProcess:
         
         # 2. HighPass Filter (Remove Rumble / DC Offset)
         if highpass_cutoff > 0:
-            # Cascade for steep "Brick Wall" effect
-            for _ in range(6):
-                waveform = F.highpass_biquad(waveform, original_rate, cutoff_freq=highpass_cutoff)
+            # Single pass (2nd order, 12dB/oct) is safer for preserving voice body.
+            # Cascading here was too aggressive and killed the bass details.
+            waveform = F.highpass_biquad(waveform, original_rate, cutoff_freq=highpass_cutoff)
 
         # 3. LowPass Filter (Anti-Aliasing / Denoise)
         if lowpass_cutoff > 0:
diff --git a/pyproject.toml b/pyproject.toml
index a8cee23..51110a0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,7 @@
 [project]
 name = "aiia"
 description = "A suite of powerful, intuitive, and highly customizable nodes for ComfyUI, featuring a high-performance Media Browser and OOM-safe video tools."
-version = "1.3.11"
+version = "1.3.12"
 license = {file = "LICENSE"}
 readme = "README.md"
 authors = [