diff --git a/abogen/gui.py b/abogen/gui.py
index 2131622..23b44ed 100644
--- a/abogen/gui.py
+++ b/abogen/gui.py
@@ -570,15 +570,9 @@ class abogen(QWidget):
         )
         voice_row.addWidget(self.voice_combo)
         
-        # voice formula - text box for now, add a dialog later
-        self.voice_formula = QTextEdit(self)
-        self.voice_formula.setAcceptRichText(False)
-        self.voice_formula.setPlaceholderText("Enter voice formula here...")
-        self.voice_formula.setText('0.242 * am_michael + 0.758 * bf_isabella')
-        voice_row.addWidget(self.voice_formula)
-
+        # Voice formula button
         self.btn_voice_formula_mixer = QPushButton(self)
-        self.btn_voice_formula_mixer.setText("☺") # TODO add voice formula icon
+        self.btn_voice_formula_mixer.setText("🛠") # TODO add voice formula icon
         self.btn_voice_formula_mixer.setToolTip("Mix and match voices")
         self.btn_voice_formula_mixer.setFixedSize(40, 36)
         self.btn_voice_formula_mixer.setStyleSheet("QPushButton { padding: 6px 12px; }")
diff --git a/abogen/voice_formula_gui.py b/abogen/voice_formula_gui.py
index 5fc166b..52a468f 100644
--- a/abogen/voice_formula_gui.py
+++ b/abogen/voice_formula_gui.py
@@ -39,6 +39,7 @@ class VoiceMixer(QWidget):
         # Checkbox at the top
         self.checkbox = QCheckBox()
         self.checkbox.setChecked(initial_status)
+        self.checkbox.stateChanged.connect(self.toggle_inputs)
         self.checkbox.stateChanged.connect(self.update_formula_callback)
         layout.addWidget(self.checkbox, alignment=Qt.AlignCenter)
 
@@ -78,7 +79,15 @@ class VoiceMixer(QWidget):
 
         layout.addLayout(slider_layout)
         self.setLayout(layout)
+
+        # Disable inputs initially if the checkbox is unchecked
+        self.toggle_inputs()
         
+    def toggle_inputs(self):
+        """Enable or disable inputs based on the checkbox state."""
+        is_enabled = self.checkbox.isChecked()
+        self.spin_box.setEnabled(is_enabled)
+        self.slider.setEnabled(is_enabled)
 
     def get_voice_gender(self):
         if self.voice_name in VOICES_INTERNAL:
@@ -133,8 +142,8 @@ class VoiceFormulaDialog(QDialog):
         cancel_button = QPushButton("Cancel")
 
         # Connect buttons to appropriate slots
-        ok_button.clicked.connect(self.accept)      # Close dialog and return QDialog.Accepted
-        cancel_button.clicked.connect(self.reject)  # Close dialog and return QDialog.Rejected
+        ok_button.clicked.connect(self.accept)      
+        cancel_button.clicked.connect(self.reject)  
 
         button_layout.addStretch()  # Push buttons to the right
         button_layout.addWidget(ok_button)