diff --git a/app/src/main/kotlin/com/tutpro/baresip/ConfigActivity.kt b/app/src/main/kotlin/com/tutpro/baresip/ConfigActivity.kt
index 050502ce..9385686f 100644
--- a/app/src/main/kotlin/com/tutpro/baresip/ConfigActivity.kt
+++ b/app/src/main/kotlin/com/tutpro/baresip/ConfigActivity.kt
@@ -92,7 +92,7 @@ class ConfigActivity : AppCompatActivity() {
         callVolAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
         callVolSpinner.adapter = callVolAdapter
         callVolSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
-            override fun onItemSelected(parent: AdapterView<*>, view: View, position: Int, id: Long) {
+            override fun onItemSelected(parent: AdapterView<*>, view: View?, position: Int, id: Long) {
                 callVolume = volVals[volKeys.indexOf(parent.selectedItem.toString())]
             }
             override fun onNothingSelected(parent: AdapterView<*>) {