diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index 153023e..f5c1360 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -2751,6 +2751,21 @@
                 io = mPlaybackThreads.keyAt(0);
             }
             ALOGV("createEffect() got io %d for effect %s", io, desc.name);
+        } else if (checkPlaybackThread_l(io) != nullptr) {
+            // allow only one effect chain per sessionId on mPlaybackThreads.
+            for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
+                const audio_io_handle_t checkIo = mPlaybackThreads.keyAt(i);
+                if (io == checkIo) continue;
+                const uint32_t sessionType =
+                        mPlaybackThreads.valueAt(i)->hasAudioSession(sessionId);
+                if ((sessionType & ThreadBase::EFFECT_SESSION) != 0) {
+                    ALOGE("%s: effect %s io %d denied because session %d effect exists on io %d",
+                            __func__, desc.name, (int)io, (int)sessionId, (int)checkIo);
+                    android_errorWriteLog(0x534e4554, "123237974");
+                    lStatus = BAD_VALUE;
+                    goto Exit;
+                }
+            }
         }
         ThreadBase *thread = checkRecordThread_l(io);
         if (thread == NULL) {