diff --git a/client/client_connection.cpp b/client/client_connection.cpp
index 20031844..da5e5262 100644
--- a/client/client_connection.cpp
+++ b/client/client_connection.cpp
@@ -93,7 +93,7 @@ bool PendingRequest::operator<(const PendingRequest& other) const
 
 
 ClientConnection::ClientConnection(boost::asio::io_context& io_context, const ClientSettings::Server& server)
-    : io_context_(io_context), strand_(boost::asio::make_strand(io_context_.get_executor())), resolver_(strand_), socket_(strand_), reqId_(1), server_(server)
+    : strand_(boost::asio::make_strand(io_context.get_executor())), resolver_(strand_), socket_(strand_), reqId_(1), server_(server)
 {
     base_msg_size_ = base_message_.getSize();
     buffer_.resize(base_msg_size_);
diff --git a/client/client_connection.hpp b/client/client_connection.hpp
index bd107934..221d5056 100644
--- a/client/client_connection.hpp
+++ b/client/client_connection.hpp
@@ -140,7 +140,6 @@ protected:
     std::vector<char> buffer_;
     size_t base_msg_size_;
 
-    boost::asio::io_context& io_context_;
     boost::asio::strand<boost::asio::any_io_executor> strand_;
     tcp::resolver resolver_;
     tcp::socket socket_;
diff --git a/server/control_server.cpp b/server/control_server.cpp
index 7c55ffb8..772f714f 100644
--- a/server/control_server.cpp
+++ b/server/control_server.cpp
@@ -55,7 +55,7 @@ ControlServer::~ControlServer()
 
 void ControlServer::cleanup()
 {
-    auto new_end = std::remove_if(sessions_.begin(), sessions_.end(), [](std::weak_ptr<ControlSession> session) { return session.expired(); });
+    auto new_end = std::remove_if(sessions_.begin(), sessions_.end(), [](const std::weak_ptr<ControlSession>& session) { return session.expired(); });
     auto count = distance(new_end, sessions_.end());
     if (count > 0)
     {
diff --git a/server/publishZeroConf/publish_mdns.hpp b/server/publishZeroConf/publish_mdns.hpp
index 83fd542e..565847b6 100644
--- a/server/publishZeroConf/publish_mdns.hpp
+++ b/server/publishZeroConf/publish_mdns.hpp
@@ -41,7 +41,7 @@ struct mDNSService
 class PublishmDNS
 {
 public:
-    PublishmDNS(const std::string& serviceName, boost::asio::io_context& ioc) : serviceName_(serviceName), ioc_(ioc)
+    PublishmDNS(const std::string& serviceName, boost::asio::io_context& ioc) : serviceName_(serviceName), io_context_(ioc)
     {
     }
 
@@ -51,7 +51,7 @@ public:
 
 protected:
     std::string serviceName_;
-    boost::asio::io_context& ioc_;
+    boost::asio::io_context& io_context_;
 };
 
 #if defined(HAS_AVAHI)
diff --git a/server/server.cpp b/server/server.cpp
index e1450f84..bf0dced9 100644
--- a/server/server.cpp
+++ b/server/server.cpp
@@ -1,6 +1,6 @@
 /***
     This file is part of snapcast
-    Copyright (C) 2014-2021  Johannes Pohl
+    Copyright (C) 2014-2022  Johannes Pohl
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -159,7 +159,6 @@ void Server::processRequest(const jsonrpcpp::request_ptr request, const OnRespon
                 // Notification: {"jsonrpc":"2.0","method":"Client.OnVolumeChanged","params":{"id":"00:21:6a:7d:74:fc","volume":{"muted":false,"percent":74}}}
                 // clang-format on
 
-                // std::lock_guard<std::recursive_mutex> lock(clientMutex_);
                 clientInfo->config.volume.fromJson(request->params().get("volume"));
                 result["volume"] = clientInfo->config.volume.toJson();
                 notification = std::make_shared<jsonrpcpp::Notification>(
@@ -636,7 +635,6 @@ void Server::processRequest(const jsonrpcpp::request_ptr request, const OnRespon
 void Server::onMessageReceived(std::shared_ptr<ControlSession> controlSession, const std::string& message, const ResponseHander& response_handler)
 {
     // LOG(DEBUG, LOG_TAG) << "onMessageReceived: " << message << "\n";
-    // std::lock_guard<std::recursive_mutex> lock(clientMutex_);
     std::lock_guard<std::mutex> lock(Config::instance().getMutex());
     jsonrpcpp::entity_ptr entity(nullptr);
     try
@@ -712,7 +710,6 @@ void Server::onMessageReceived(std::shared_ptr<ControlSession> controlSession, c
 
 void Server::onMessageReceived(StreamSession* streamSession, const msg::BaseMessage& baseMessage, char* buffer)
 {
-    // std::lock_guard<std::recursive_mutex> lock(clientMutex_);
     LOG(DEBUG, LOG_TAG) << "onMessageReceived: " << baseMessage.type << ", size: " << baseMessage.size << ", id: " << baseMessage.id
                         << ", refers: " << baseMessage.refersTo << ", sent: " << baseMessage.sent.sec << "," << baseMessage.sent.usec
                         << ", recv: " << baseMessage.received.sec << "," << baseMessage.received.usec << "\n";
diff --git a/server/server.hpp b/server/server.hpp
index e916c6c5..bcd4ba39 100644
--- a/server/server.hpp
+++ b/server/server.hpp
@@ -93,8 +93,6 @@ private:
     /// @param deferred the delay after the last call to saveConfig
     void saveConfig(const std::chrono::milliseconds& deferred = std::chrono::seconds(2));
 
-    // mutable std::recursive_mutex controlMutex_;
-    // mutable std::recursive_mutex clientMutex_;
     boost::asio::io_context& io_context_;
     boost::asio::steady_timer config_timer_;
 
diff --git a/server/stream_server.hpp b/server/stream_server.hpp
index 5b6eec94..284e210c 100644
--- a/server/stream_server.hpp
+++ b/server/stream_server.hpp
@@ -86,7 +86,6 @@ private:
     void onDisconnect(StreamSession* streamSession) override;
 
     mutable std::recursive_mutex sessionsMutex_;
-    // mutable std::recursive_mutex clientMutex_;
     std::vector<std::weak_ptr<StreamSession>> sessions_;
     boost::asio::io_context& io_context_;
     std::vector<acceptor_ptr> acceptor_;
diff --git a/server/streamreader/pcm_stream.cpp b/server/streamreader/pcm_stream.cpp
index a412274d..e1217fb7 100644
--- a/server/streamreader/pcm_stream.cpp
+++ b/server/streamreader/pcm_stream.cpp
@@ -46,7 +46,7 @@ static constexpr auto LOG_TAG = "PcmStream";
 
 PcmStream::PcmStream(PcmStream::Listener* pcmListener, boost::asio::io_context& ioc, const ServerSettings& server_settings, const StreamUri& uri)
     : active_(false), strand_(boost::asio::make_strand(ioc.get_executor())), pcmListeners_{pcmListener}, uri_(uri), chunk_ms_(20), state_(ReaderState::kIdle),
-      ioc_(ioc), server_settings_(server_settings), req_id_(0), property_timer_(strand_)
+      server_settings_(server_settings), req_id_(0), property_timer_(strand_)
 {
     encoder::EncoderFactory encoderFactory;
     if (uri_.query.find(kUriCodec) == uri_.query.end())
diff --git a/server/streamreader/pcm_stream.hpp b/server/streamreader/pcm_stream.hpp
index d33a27be..29839e83 100644
--- a/server/streamreader/pcm_stream.hpp
+++ b/server/streamreader/pcm_stream.hpp
@@ -189,7 +189,6 @@ protected:
     std::string name_;
     std::atomic<ReaderState> state_;
     Properties properties_;
-    boost::asio::io_context& ioc_;
     ServerSettings server_settings_;
     std::unique_ptr<StreamControl> stream_ctrl_;
     std::atomic<int> req_id_;
diff --git a/server/streamreader/stream_manager.cpp b/server/streamreader/stream_manager.cpp
index d10fce41..2b9a82d4 100644
--- a/server/streamreader/stream_manager.cpp
+++ b/server/streamreader/stream_manager.cpp
@@ -1,6 +1,6 @@
 /***
     This file is part of snapcast
-    Copyright (C) 2014-2021  Johannes Pohl
+    Copyright (C) 2014-2022  Johannes Pohl
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -47,7 +47,7 @@ namespace streamreader
 
 StreamManager::StreamManager(PcmStream::Listener* pcmListener, boost::asio::io_context& ioc, const ServerSettings& settings)
     // const std::string& defaultSampleFormat, const std::string& defaultCodec, size_t defaultChunkBufferMs)
-    : pcmListener_(pcmListener), settings_(settings), ioc_(ioc)
+    : pcmListener_(pcmListener), settings_(settings), io_context_(ioc)
 {
 }
 
@@ -79,20 +79,20 @@ PcmStreamPtr StreamManager::addStream(StreamUri& streamUri)
 
     if (streamUri.scheme == "pipe")
     {
-        stream = make_shared<PipeStream>(pcmListener_, ioc_, settings_, streamUri);
+        stream = make_shared<PipeStream>(pcmListener_, io_context_, settings_, streamUri);
     }
     else if (streamUri.scheme == "file")
     {
-        stream = make_shared<FileStream>(pcmListener_, ioc_, settings_, streamUri);
+        stream = make_shared<FileStream>(pcmListener_, io_context_, settings_, streamUri);
     }
     else if (streamUri.scheme == "process")
     {
-        stream = make_shared<ProcessStream>(pcmListener_, ioc_, settings_, streamUri);
+        stream = make_shared<ProcessStream>(pcmListener_, io_context_, settings_, streamUri);
     }
 #ifdef HAS_ALSA
     else if (streamUri.scheme == "alsa")
     {
-        stream = make_shared<AlsaStream>(pcmListener_, ioc_, settings_, streamUri);
+        stream = make_shared<AlsaStream>(pcmListener_, io_context_, settings_, streamUri);
     }
 #endif
     else if ((streamUri.scheme == "spotify") || (streamUri.scheme == "librespot"))
@@ -101,7 +101,7 @@ PcmStreamPtr StreamManager::addStream(StreamUri& streamUri)
         // that all constructors of all parent classes also use the overwritten sample
         // format.
         streamUri.query[kUriSampleFormat] = "44100:16:2";
-        stream = make_shared<LibrespotStream>(pcmListener_, ioc_, settings_, streamUri);
+        stream = make_shared<LibrespotStream>(pcmListener_, io_context_, settings_, streamUri);
     }
     else if (streamUri.scheme == "airplay")
     {
@@ -109,15 +109,15 @@ PcmStreamPtr StreamManager::addStream(StreamUri& streamUri)
         // that all constructors of all parent classes also use the overwritten sample
         // format.
         streamUri.query[kUriSampleFormat] = "44100:16:2";
-        stream = make_shared<AirplayStream>(pcmListener_, ioc_, settings_, streamUri);
+        stream = make_shared<AirplayStream>(pcmListener_, io_context_, settings_, streamUri);
     }
     else if (streamUri.scheme == "tcp")
     {
-        stream = make_shared<TcpStream>(pcmListener_, ioc_, settings_, streamUri);
+        stream = make_shared<TcpStream>(pcmListener_, io_context_, settings_, streamUri);
     }
     else if (streamUri.scheme == "meta")
     {
-        stream = make_shared<MetaStream>(pcmListener_, streams_, ioc_, settings_, streamUri);
+        stream = make_shared<MetaStream>(pcmListener_, streams_, io_context_, settings_, streamUri);
     }
     else
     {
diff --git a/server/streamreader/stream_manager.hpp b/server/streamreader/stream_manager.hpp
index 3b9fda5d..e82bf6b8 100644
--- a/server/streamreader/stream_manager.hpp
+++ b/server/streamreader/stream_manager.hpp
@@ -1,6 +1,6 @@
 /***
     This file is part of snapcast
-    Copyright (C) 2014-2021  Johannes Pohl
+    Copyright (C) 2014-2022  Johannes Pohl
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -55,7 +55,7 @@ private:
     std::vector<PcmStreamPtr> streams_;
     PcmStream::Listener* pcmListener_;
     ServerSettings settings_;
-    boost::asio::io_context& ioc_;
+    boost::asio::io_context& io_context_;
 };
 
 } // namespace streamreader