diff --git a/media/libeffects/preprocessing/PreProcessing.cpp b/media/libeffects/preprocessing/PreProcessing.cpp
index 61a2bf5..59f1fc3 100644
--- a/media/libeffects/preprocessing/PreProcessing.cpp
+++ b/media/libeffects/preprocessing/PreProcessing.cpp
@@ -102,7 +102,8 @@
     uint32_t state;                // current state (enum preproc_session_state)
     int id;                        // audio session ID
     int io;                        // handle of input stream this session is on
-    webrtc::AudioProcessing* apm;  // handle on webRTC audio processing module (APM)
+    rtc::scoped_refptr<webrtc::AudioProcessing>
+            apm;  // handle on webRTC audio processing module (APM)
     // Audio Processing module builder
     webrtc::AudioProcessingBuilder ap_builder;
     // frameCount represents the size of the buffers used for processing, and must represent 10ms.
@@ -260,9 +261,6 @@
     ALOGV("Agc2Init");
     effect->session->config = effect->session->apm->GetConfig();
     effect->session->config.gain_controller2.fixed_digital.gain_db = 0.f;
-    effect->session->config.gain_controller2.adaptive_digital.level_estimator =
-            effect->session->config.gain_controller2.kRms;
-    effect->session->config.gain_controller2.adaptive_digital.extra_saturation_margin_db = 2.f;
     effect->session->apm->ApplyConfig(effect->session->config);
     return 0;
 }
@@ -332,24 +330,19 @@
             ALOGV("Agc2GetParameter() target level %f dB", *(float*)pValue);
             break;
         case AGC2_PARAM_ADAPT_DIGI_LEVEL_ESTIMATOR:
-            *(uint32_t*)pValue = (uint32_t)(
-                    effect->session->config.gain_controller2.adaptive_digital.level_estimator);
-            ALOGV("Agc2GetParameter() level estimator %d",
-                  *(webrtc::AudioProcessing::Config::GainController2::LevelEstimator*)pValue);
+            // WebRTC only supports RMS level estimator now
+            *(uint32_t*)pValue = (uint32_t)(0);
+            ALOGV("Agc2GetParameter() level estimator RMS");
             break;
         case AGC2_PARAM_ADAPT_DIGI_EXTRA_SATURATION_MARGIN:
-            *(float*)pValue = (float)(effect->session->config.gain_controller2.adaptive_digital
-                                              .extra_saturation_margin_db);
+            *(float*)pValue = (float)(2.0);
             ALOGV("Agc2GetParameter() extra saturation margin %f dB", *(float*)pValue);
             break;
         case AGC2_PARAM_PROPERTIES:
             pProperties->fixedDigitalGain =
                     (float)(effect->session->config.gain_controller2.fixed_digital.gain_db);
-            pProperties->level_estimator = (uint32_t)(
-                    effect->session->config.gain_controller2.adaptive_digital.level_estimator);
-            pProperties->extraSaturationMargin =
-                    (float)(effect->session->config.gain_controller2.adaptive_digital
-                                    .extra_saturation_margin_db);
+            pProperties->level_estimator = 0;
+            pProperties->extraSaturationMargin = 2.0;
             break;
         default:
             ALOGW("Agc2GetParameter() unknown param %d", param);
@@ -438,16 +431,19 @@
             effect->session->config.gain_controller2.fixed_digital.gain_db = valueFloat;
             break;
         case AGC2_PARAM_ADAPT_DIGI_LEVEL_ESTIMATOR:
-            ALOGV("Agc2SetParameter() level estimator %d",
-                  *(webrtc::AudioProcessing::Config::GainController2::LevelEstimator*)pValue);
-            effect->session->config.gain_controller2.adaptive_digital.level_estimator =
-                    (*(webrtc::AudioProcessing::Config::GainController2::LevelEstimator*)pValue);
+            ALOGV("Agc2SetParameter() level estimator %d", *(uint32_t*)pValue);
+            if (*(uint32_t*)pValue != 0) {
+              // only RMS is supported
+              status = -EINVAL;
+            }
             break;
         case AGC2_PARAM_ADAPT_DIGI_EXTRA_SATURATION_MARGIN:
             valueFloat = (float)(*(int32_t*)pValue);
             ALOGV("Agc2SetParameter() extra saturation margin %f dB", valueFloat);
-            effect->session->config.gain_controller2.adaptive_digital.extra_saturation_margin_db =
-                    valueFloat;
+            if (valueFloat != 2.0) {
+              // extra_staturation_margin_db is no longer configurable in webrtc
+              status = -EINVAL;
+            }
             break;
         case AGC2_PARAM_PROPERTIES:
             ALOGV("Agc2SetParameter() properties gain %f, level %d margin %f",
@@ -455,11 +451,9 @@
                   pProperties->extraSaturationMargin);
             effect->session->config.gain_controller2.fixed_digital.gain_db =
                     pProperties->fixedDigitalGain;
-            effect->session->config.gain_controller2.adaptive_digital.level_estimator =
-                    (webrtc::AudioProcessing::Config::GainController2::LevelEstimator)
-                            pProperties->level_estimator;
-            effect->session->config.gain_controller2.adaptive_digital.extra_saturation_margin_db =
-                    pProperties->extraSaturationMargin;
+            if (pProperties->level_estimator != 0 || pProperties->extraSaturationMargin != 2.0) {
+              status = -EINVAL;
+            }
             break;
         default:
             ALOGW("Agc2SetParameter() unknown param %08x value %08x", param, *(uint32_t*)pValue);
@@ -879,8 +873,8 @@
 
 error:
     if (session->createdMsk == 0) {
-        delete session->apm;
-        session->apm = NULL;
+        // Scoped_refptr will handle reference counting here
+        session->apm = nullptr;
     }
     return status;
 }
@@ -889,8 +883,8 @@
     ALOGW_IF(Effect_Release(fx) != 0, " Effect_Release() failed for proc ID %d", fx->procId);
     session->createdMsk &= ~(1 << fx->procId);
     if (session->createdMsk == 0) {
-        delete session->apm;
-        session->apm = NULL;
+        // Scoped_refptr will handle reference counting here
+        session->apm = nullptr;
         session->id = 0;
     }
 
diff --git a/media/libeffects/preprocessing/tests/EffectPreprocessingTest.cpp b/media/libeffects/preprocessing/tests/EffectPreprocessingTest.cpp
index 07006a1..8fdb864 100644
--- a/media/libeffects/preprocessing/tests/EffectPreprocessingTest.cpp
+++ b/media/libeffects/preprocessing/tests/EffectPreprocessingTest.cpp
@@ -143,10 +143,6 @@
         const AGC2Params* agc2Params = &params->agc2Params;
         ASSERT_NO_FATAL_FAILURE(
                 effect.setParam(AGC2_PARAM_FIXED_DIGITAL_GAIN, agc2Params->fixedDigitalGain));
-        ASSERT_NO_FATAL_FAILURE(effect.setParam(AGC2_PARAM_ADAPT_DIGI_LEVEL_ESTIMATOR,
-                                                agc2Params->adaptDigiLevelEstimator));
-        ASSERT_NO_FATAL_FAILURE(effect.setParam(AGC2_PARAM_ADAPT_DIGI_EXTRA_SATURATION_MARGIN,
-                                                agc2Params->extraSaturationMargin));
     } else if (isAECEffect(uuid)) {
         const AECParams* aecParams = &params->aecParams;
         ASSERT_NO_FATAL_FAILURE(effect.setParam(AEC_PARAM_ECHO_DELAY, aecParams->echoDelay));
diff --git a/media/libeffects/preprocessing/tests/PreProcessingTest.cpp b/media/libeffects/preprocessing/tests/PreProcessingTest.cpp
index 3bd93f8..03400d7 100644
--- a/media/libeffects/preprocessing/tests/PreProcessingTest.cpp
+++ b/media/libeffects/preprocessing/tests/PreProcessingTest.cpp
@@ -400,20 +400,6 @@
             ALOGE("Invalid AGC2 Fixed Digital Gain. Error %d\n", status);
             return EXIT_FAILURE;
         }
-        if (int status = preProcSetConfigParam(AGC2_PARAM_ADAPT_DIGI_LEVEL_ESTIMATOR,
-                                               (uint32_t)preProcCfgParams.agc2Level,
-                                               effectHandle[PREPROC_AGC2]);
-            status != 0) {
-            ALOGE("Invalid AGC2 Level Estimator. Error %d\n", status);
-            return EXIT_FAILURE;
-        }
-        if (int status = preProcSetConfigParam(AGC2_PARAM_ADAPT_DIGI_EXTRA_SATURATION_MARGIN,
-                                               (float)preProcCfgParams.agc2SaturationMargin,
-                                               effectHandle[PREPROC_AGC2]);
-            status != 0) {
-            ALOGE("Invalid AGC2 Saturation Margin. Error %d\n", status);
-            return EXIT_FAILURE;
-        }
     }
     if (effectEn[PREPROC_NS]) {
         if (int status = preProcSetConfigParam(NS_PARAM_LEVEL, (uint32_t)preProcCfgParams.nsLevel,