diff --git a/source/Client.cpp b/source/Client.cpp
index d15e815..36f22c6 100644
--- a/source/Client.cpp
+++ b/source/Client.cpp
@@ -30,7 +30,7 @@ Client::Client(const int channels, const double rate) {
         nullptr,
         nullptr
     ) != paNoError)
-        throw std::runtime_error("Could not open PortAudio stream.");
+        throw std::runtime_error("[Client] Could not open PortAudio stream.");
 }
 
 Client::~Client() {
@@ -57,7 +57,7 @@ void Client::loopReceiver() {
         0
     );
     if (clientSocket < 0)
-        throw std::runtime_error("Could not create the socket." + std::string(gai_strerror(errno)));
+        throw std::runtime_error("[Client] Could not create the socket." + std::string(gai_strerror(errno)));
 
     // get the broadcast address
     addrinfo serverHints = {};
@@ -73,7 +73,7 @@ void Client::loopReceiver() {
         &serverHints,
         &serverInfo
     ) != 0)
-        throw std::runtime_error("Could not get the address.\n" + std::string(gai_strerror(errno)));
+        throw std::runtime_error("[Client] Could not get the address: " + std::string(gai_strerror(errno)));
 
     // bind the socket to the address
     if (bind(
@@ -81,7 +81,7 @@ void Client::loopReceiver() {
         serverInfo->ai_addr,
         serverInfo->ai_addrlen
     ) < 0)
-        throw std::runtime_error("Could not bind to the address.");
+        throw std::runtime_error("[Client] Could not bind to the address." + std::string(gai_strerror(errno)));
 
     // free the server address
     freeaddrinfo(serverInfo);
@@ -104,12 +104,12 @@ void Client::loopReceiver() {
             &serverAddressLength
         );
         if (size == -1) {
-            std::cerr << "Could not receive from the socket : " << gai_strerror(errno) << std::endl;
+            std::cerr << "[Client] Could not receive from the socket: " << gai_strerror(errno) << std::endl;
             continue;
         }
 
         // save the audio data into the queue for the player
-        std::cout << "[Client] received : " << size << " bytes" << std::endl;
+        std::cout << "[Client] Received: " << size << " bytes" << std::endl;
         this->audioQueue.push(audioPacket);
         // notify that a new audio chunk is available
         this->audioCondition.notify_one();
@@ -117,10 +117,6 @@ void Client::loopReceiver() {
 }
 
 void Client::loopPlayer() {
-    // start the PortAudio stream
-    if (Pa_StartStream(this->stream) != paNoError)
-        throw std::runtime_error("Could not start the PortAudio stream.");
-
     while (true) {
         // wait for a new element in the audio queue
         this->audioCondition.wait(
@@ -132,10 +128,10 @@ void Client::loopPlayer() {
         // wait until it must be played
         std::this_thread::sleep_until(audioPacket.timePlay);
 
-        // TODO(Faraphel): check for the error ?
         // TODO(Faraphel) / 2 => / encoding size
         // TODO(Faraphel): the number of frames could be improved
-        // TODO(Faraphel): more comments
+
+        std::cout << "[Client] Playing: " << audioPacket.timePlay << std::endl;
 
         std::cout << "playing: " << audioPacket.timePlay << std::endl;
 
@@ -148,13 +144,13 @@ void Client::loopPlayer() {
         switch (error) {
             // success
             case paNoError:
-            // the output might be very slightly underflowed,
+            // the output might be very slightly underflown,
             // causing a very small period where no noise will be played.
             case paOutputUnderflowed:
                 break;
 
             default:
-                std::cerr << "Could not write to the PortAudio stream." << Pa_GetErrorText(error) << std::endl;
+                std::cerr << "[Client] Could not write to the PortAudio stream: " << Pa_GetErrorText(error) << std::endl;
         }
 
         // remove the audio chunk
diff --git a/source/Client.hpp b/source/Client.hpp
index 24925bf..5210a59 100644
--- a/source/Client.hpp
+++ b/source/Client.hpp
@@ -18,15 +18,33 @@ struct AudioPacketsComparator {
 };
 
 
+/**
+ * the audio Client.
+ * Receive audio packets and play them at a specific time.
+ */
 class Client {
 public:
+    /**
+    * :param channels: the number of channel in the audio
+    * :param rate: the rate of the audio
+    */
     explicit Client(int channels, double rate);
     ~Client();
 
+    /**
+     * Indefinitely receive and play audio data.
+     */
     void loop();
 
 private:
+    /**
+     * Indefinitely receive audio data.
+     */
     void loopReceiver();
+
+    /**
+     * Indefinitely play audio data.
+     */
     void loopPlayer();
 
     PaStream* stream;
diff --git a/source/Server.cpp b/source/Server.cpp
index a19cedb..6b1b0fc 100644
--- a/source/Server.cpp
+++ b/source/Server.cpp
@@ -17,13 +17,15 @@ Server::Server() {
     // create a new mpg123 handle
     int error;
     this->mpgHandle = mpg123_new(nullptr, &error);
+    if (this->mpgHandle == nullptr)
+        throw std::runtime_error("[Server] Could not create a mpg123 handle.");
 
     // open the mp3 file
     if (mpg123_open(
         this->mpgHandle,
         "./assets/Caravan Palace - Wonderland.mp3"
     ))
-        throw std::runtime_error("Could not open file.");
+        throw std::runtime_error("[Server] Could not open file.");
 
     // get the format of the file
     if (mpg123_getformat(
@@ -32,7 +34,7 @@ Server::Server() {
         &this->channels,
         &this->encoding
     ) != MPG123_OK)
-        throw std::runtime_error("Could not get the format of the file.");
+        throw std::runtime_error("[Server] Could not get the format of the file.");
 }
 
 Server::~Server() {
@@ -42,8 +44,6 @@ Server::~Server() {
 }
 
 void Server::loop() {
-    int error;
-
     // get the broadcast address
     addrinfo broadcastHints {};
     broadcastHints.ai_family = AF_INET6;
@@ -52,13 +52,13 @@ void Server::loop() {
 
     // TODO(Faraphel): ip / port as argument
     addrinfo *broadcastInfo;
-    if((error = getaddrinfo(
+    if(const int error = getaddrinfo(
         "::1",
         "5650",
         &broadcastHints,
         &broadcastInfo
-    )) != 0)
-        throw std::runtime_error("Could not get the address.\n" + std::string(gai_strerror(error)));
+    ) != 0)
+        throw std::runtime_error("[Server] Could not get the address: " + std::string(gai_strerror(error)));
 
     const int broadcastSocket = socket(
         broadcastInfo->ai_family,
@@ -66,7 +66,7 @@ void Server::loop() {
         broadcastInfo->ai_protocol
     );
     if (broadcastSocket == -1)
-        throw std::runtime_error("Could not create the socket: " + std::string(gai_strerror(errno)));
+        throw std::runtime_error("[Server] Could not create the socket: " + std::string(gai_strerror(errno)));
 
     // read the file
     AudioPacket audioPacket;
@@ -93,10 +93,12 @@ void Server::loop() {
             0,
             broadcastInfo->ai_addr,
             broadcastInfo->ai_addrlen
-        ) == -1)
-            std::cerr << "Could not send audio packet : " << strerror(errno) << std::endl;
-        else
-            std::cout << "[Server] sent : " << done << " bytes" << std::endl;
+        ) == -1) {
+            std::cerr << "[Server] Could not send audio packet: " << strerror(errno) << std::endl;
+            continue;
+        }
+
+        std::cout << "[Server] Sent: " << done << " bytes" << std::endl;
 
         // wait 10ms to simulate lag
         // TODO(Faraphel): should be extended to simulate live music streaming
diff --git a/source/Server.hpp b/source/Server.hpp
index 5f80248..bb7d11d 100644
--- a/source/Server.hpp
+++ b/source/Server.hpp
@@ -2,15 +2,34 @@
 #include <mpg123.h>
 
 
+/**
+ * the audio Server.
+ * Read and broadcast audio data.
+ */
 class Server {
 public:
     explicit Server();
     ~Server();
 
+    /**
+     * Indefinitely read and broadcast audio data.
+     */
     void loop();
 
+    /**
+     * get the current rate of the audio data.
+     * @return the current rate of the audio data.
+     */
     long getRate() const;
+    /**
+     * get the current number of channels of the audio data.
+     * @return the current number of channels of the audio data.
+     */
     int getChannels() const;
+    /**
+     * get the current encoding of the audio data.
+     * @return the current encoding of the audio data.
+     */
     int getEncoding() const;
 
 private: