diff --git a/src/shim.cpp b/src/shim.cpp
index 78f1da1..6065afa 100644
--- a/src/shim.cpp
+++ b/src/shim.cpp
@@ -29,20 +29,42 @@ static void init_libcutils() {
     }
 
     ashmem_create_region = dlsym(libcutils, "ashmem_create_region");
-    ashmem_set_prot_region = dlsym(libcutils, "ashmem_set_prot_region");
-
-    native_handle_create = dlsym(libcutils, "native_handle_create");
-    native_handle_close = dlsym(libcutils, "native_handle_close");
-    native_handle_delete = dlsym(libcutils, "native_handle_delete");
-
-    if (ashmem_create_region == nullptr ||
-        ashmem_set_prot_region == nullptr ||
-        native_handle_create == nullptr ||
-        native_handle_close == nullptr ||
-        native_handle_delete == nullptr) {
-        ALOGE("Failed to load symbols from libcutils.so");
+    if (ashmem_create_region == nullptr) {
+        ALOGE("Failed to load symbol ashmem_create_region from libcutils.so");
+        goto exit;
     }
 
+    ashmem_set_prot_region = dlsym(libcutils, "ashmem_set_prot_region");
+    if (ashmem_set_prot_region == nullptr) {
+        ALOGE("Failed to load symbol ashmem_set_prot_region from libcutils.so");
+        goto exit;
+    }
+
+    native_handle_create = dlsym(libcutils, "native_handle_create");
+    if (native_handle_create == nullptr) {
+        ALOGE("Failed to load symbol native_handle_create from libcutils.so");
+        goto exit;
+    }
+
+    native_handle_close = dlsym(libcutils, "native_handle_close");
+    if (native_handle_close == nullptr) {
+        ALOGE("Failed to load symbol native_handle_close from libcutils.so");
+        goto exit;
+    }
+
+    native_handle_delete = dlsym(libcutils, "native_handle_delete");
+    if (native_handle_delete == nullptr) {
+        ALOGE("Failed to load symbol native_handle_delete from libcutils.so");
+        goto exit;
+    }
+
+    ALOGD("ashmem_create_region: %p", ashmem_create_region);
+    ALOGD("ashmem_set_prot_region: %p", ashmem_set_prot_region);
+    ALOGD("native_handle_create: %p", native_handle_create);
+    ALOGD("native_handle_close: %p", native_handle_close);
+    ALOGD("native_handle_delete: %p", native_handle_delete);
+
+exit:
     dlclose(libcutils);
 }
 
@@ -54,26 +76,42 @@ static void init_libfmq() {
     }
 
     _ZN7android8hardware7details5checkEbPKc = dlsym(libfmq, "_ZN7android8hardware7details5checkEbPKc");
-    // ndk variant, real symbol: _ZN7android8hardware7details8logErrorERKNSt3__112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE
-    _ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE = dlsym(libfmq, "_ZN7android8hardware7details8logErrorERKNSt3__112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE");
-    // ndk variant, real symbol: _ZN7android8hardware9EventFlag15createEventFlagEPNSt3__16atomicIjEEPPS1_
-    _ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_ = dlsym(libfmq, "_ZN7android8hardware9EventFlag15createEventFlagEPNSt3__16atomicIjEEPPS1_");
-    _ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_ = dlsym(libfmq, "_ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_");
-
-    if (_ZN7android8hardware7details5checkEbPKc == nullptr ||
-        _ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE == nullptr ||
-        _ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_ == nullptr ||
-        _ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_ == nullptr) {
-        ALOGE("Failed to load symbols from libfmq.so");
+    if (_ZN7android8hardware7details5checkEbPKc == nullptr) {
+        ALOGE("Failed to load symbol _ZN7android8hardware7details5checkEbPKc from libfmq.so");
+        goto exit;
     }
 
+    // ndk variant, real symbol: _ZN7android8hardware7details8logErrorERKNSt3__112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE
+    _ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE = dlsym(libfmq, "_ZN7android8hardware7details8logErrorERKNSt3__112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE");
+    if (_ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE == nullptr) {
+        ALOGE("Failed to load symbol _ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE from libfmq.so");
+        goto exit;
+    }
+
+    // ndk variant, real symbol: _ZN7android8hardware9EventFlag15createEventFlagEPNSt3__16atomicIjEEPPS1_
+    _ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_ = dlsym(libfmq, "_ZN7android8hardware9EventFlag15createEventFlagEPNSt3__16atomicIjEEPPS1_");
+    if (_ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_ == nullptr) {
+        ALOGE("Failed to load symbol _ZN7android8hardware9EventFlag15createEventFlagEPNSt3__16atomicIjEEPPS1_ from libfmq.so");
+        goto exit;
+    }
+
+    _ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_ = dlsym(libfmq, "_ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_");
+    if (_ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_ == nullptr) {
+        ALOGE("Failed to load symbol _ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_ from libfmq.so");
+        goto exit;
+    }
+
+    ALOGD("_ZN7android8hardware7details5checkEbPKc: %p", _ZN7android8hardware7details5checkEbPKc);
+    ALOGD("_ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE: %p", _ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE);
+    ALOGD("_ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_: %p", _ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_);
+    ALOGD("_ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_: %p", _ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_);
+
+exit:
     dlclose(libfmq);
 }
 
 __attribute__((constructor))
 void shim_init() {
-    ALOGD("shim_init");
     init_libcutils();
     init_libfmq();
-    ALOGD("shim_init done");
 }
\ No newline at end of file
diff --git a/src/viper_aidl.cpp b/src/viper_aidl.cpp
index d72de4e..f8587c1 100644
--- a/src/viper_aidl.cpp
+++ b/src/viper_aidl.cpp
@@ -129,13 +129,17 @@ constexpr size_t getFrameSizeInBytes(
 ndk::ScopedAStatus ViPER4AndroidAIDL::open(const Parameter::Common &common,
                                            const std::optional<Parameter::Specific> &specific,
                                            IEffect::OpenEffectReturn *ret) {
-    if (common.input.base.format.pcm != PcmType::FLOAT_32_BIT) {
+    ALOGD("open called");
+    if (common.input.base.format.pcm != PcmType::FLOAT_32_BIT ||
+        common.output.base.format.pcm != PcmType::FLOAT_32_BIT) {
         ALOGE("open called with invalid PCM type");
         return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
     }
 
     std::lock_guard lg(mImplMutex);
 
+    ALOGD("mImplMutex locked");
+
     if (mState != State::INIT) {
         ALOGD("open: already opened");
         return ndk::ScopedAStatus::ok();
@@ -149,11 +153,23 @@ ndk::ScopedAStatus ViPER4AndroidAIDL::open(const Parameter::Common &common,
     size_t inBufferSizeInFloat = common.input.frameCount * mInputFrameSize / sizeof(float);
     size_t outBufferSizeInFloat = common.output.frameCount * mOutputFrameSize / sizeof(float);
 
+    ALOGD("open: inBufferSizeInFloat %zu, outBufferSizeInFloat %zu", inBufferSizeInFloat,
+          outBufferSizeInFloat);
+
     // only status FMQ use the EventFlag
     mStatusMQ = std::make_shared<StatusMQ>(1, true /*configureEventFlagWord*/);
     mInputMQ = std::make_shared<DataMQ>(inBufferSizeInFloat);
     mOutputMQ = std::make_shared<DataMQ>(outBufferSizeInFloat);
 
+    if (!mStatusMQ || !mInputMQ || !mOutputMQ) {
+        ALOGE("open: failed to create message queues");
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
+    }
+
+    ALOGD("message queues created");
+    ALOGD("open: mStatusMQ %p, mInputMQ %p, mOutputMQ %p", mStatusMQ.get(), mInputMQ.get(),
+          mOutputMQ.get());
+
     if (!mStatusMQ->isValid() || !mInputMQ->isValid() || !mOutputMQ->isValid()) {
         ALOGE("open: failed to create message queues");
         return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
@@ -166,23 +182,33 @@ ndk::ScopedAStatus ViPER4AndroidAIDL::open(const Parameter::Common &common,
         return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
     }
 
+    ALOGD("open: event flag created");
+
     mWorkBuffer.resize(std::max(inBufferSizeInFloat, outBufferSizeInFloat));
 
+    ALOGD("open: work buffer size %zu", mWorkBuffer.size());
+
     if (specific.has_value()) {
         ALOGD("open: specific parameters provided, ignoring for now...");
     }
 
     mState = State::IDLE;
 
+    ALOGD("open: state set to IDLE");
+
     ret->statusMQ = mStatusMQ->dupeDesc();
     ret->inputDataMQ = mInputMQ->dupeDesc();
     ret->outputDataMQ = mOutputMQ->dupeDesc();
 
+    ALOGD("open: mq descriptors set");
+
     if (createThread(VIPER_NAME) != RetCode::SUCCESS) {
         ALOGE("open: failed to create thread");
         return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
     }
 
+    ALOGD("open: thread created");
+
     return ndk::ScopedAStatus::ok();
 }