diff --git a/radio/IRadio.cpp b/radio/IRadio.cpp
index 0881a91..ebf3859 100644
--- a/radio/IRadio.cpp
+++ b/radio/IRadio.cpp
@@ -112,7 +112,7 @@
         if (status == NO_ERROR) {
             status = (status_t)reply.readInt32();
             if (status == NO_ERROR) {
-                int muteread = reply.readInt32();
+                int32_t muteread = reply.readInt32();
                 *mute = muteread != 0;
             }
         }
@@ -145,12 +145,12 @@
         return status;
     }
 
-    virtual status_t tune(unsigned int channel, unsigned int subChannel)
+    virtual status_t tune(uint32_t channel, uint32_t subChannel)
     {
         Parcel data, reply;
         data.writeInterfaceToken(IRadio::getInterfaceDescriptor());
-        data.writeInt32(channel);
-        data.writeInt32(subChannel);
+        data.writeUint32(channel);
+        data.writeUint32(subChannel);
         status_t status = remote()->transact(TUNE, data, &reply);
         if (status == NO_ERROR) {
             status = (status_t)reply.readInt32();
@@ -177,27 +177,29 @@
         }
         radio_metadata_t *metadata = info->metadata;
         data.writeInterfaceToken(IRadio::getInterfaceDescriptor());
+        if (metadata != NULL) {
+            data.writeUint32(1);
+        } else {
+            data.writeUint32(0);
+        }
         status_t status = remote()->transact(GET_PROGRAM_INFORMATION, data, &reply);
         if (status == NO_ERROR) {
             status = (status_t)reply.readInt32();
             if (status == NO_ERROR) {
                 reply.read(info, sizeof(struct radio_program_info));
+                // restore local metadata pointer
                 info->metadata = metadata;
-                if (metadata == NULL) {
-                    return status;
+
+                uint32_t metatataSize = reply.readUint32();
+                if ((metadata != NULL) && (metatataSize != 0)) {
+                    radio_metadata_t *newMetadata = (radio_metadata_t *)malloc(metatataSize);
+                    if (newMetadata == NULL) {
+                        return NO_MEMORY;
+                    }
+                    reply.read(newMetadata, metatataSize);
+                    status = radio_metadata_add_metadata(&info->metadata, newMetadata);
+                    free(newMetadata);
                 }
-                size_t size = (size_t)reply.readInt32();
-                if (size == 0) {
-                    return status;
-                }
-                metadata =
-                    (radio_metadata_t *)calloc(size / sizeof(unsigned int), sizeof(unsigned int));
-                if (metadata == NULL) {
-                    return NO_MEMORY;
-                }
-                reply.read(metadata, size);
-                status = radio_metadata_add_metadata(&info->metadata, metadata);
-                free(metadata);
             }
         }
         return status;
@@ -288,8 +290,8 @@
         }
         case TUNE: {
             CHECK_INTERFACE(IRadio, data, reply);
-            unsigned int channel = (unsigned int)data.readInt32();
-            unsigned int subChannel = (unsigned int)data.readInt32();
+            uint32_t channel = data.readUint32();
+            uint32_t subChannel = data.readUint32();
             status_t status = tune(channel, subChannel);
             reply->writeInt32(status);
             return NO_ERROR;
@@ -303,22 +305,27 @@
         case GET_PROGRAM_INFORMATION: {
             CHECK_INTERFACE(IRadio, data, reply);
             struct radio_program_info info;
-
-            status_t status = radio_metadata_allocate(&info.metadata, 0, 0);
-            if (status != NO_ERROR) {
-                return status;
+            status_t status;
+            // query metadata only if requested by remote side
+            if (data.readUint32() == 1) {
+                status = radio_metadata_allocate(&info.metadata, 0, 0);
+                if (status != NO_ERROR) {
+                    return status;
+                }
+            } else {
+                info.metadata = NULL;
             }
             status = getProgramInformation(&info);
+
             reply->writeInt32(status);
             if (status == NO_ERROR) {
                 reply->write(&info, sizeof(struct radio_program_info));
-                int count = radio_metadata_get_count(info.metadata);
-                if (count > 0) {
+                if ((info.metadata != NULL) && (radio_metadata_get_count(info.metadata) > 0)) {
                     size_t size = radio_metadata_get_size(info.metadata);
-                    reply->writeInt32(size);
+                    reply->writeUint32((uint32_t)size);
                     reply->write(info.metadata, size);
                 } else {
-                    reply->writeInt32(0);
+                    reply->writeUint32(0);
                 }
             }
             radio_metadata_deallocate(info.metadata);