/// <summary>
        /// Unregister a new <see cref="AudioInputSystem"/>.
        /// </summary>
        /// <param name="input">The <see cref="AudioInputSystem"/> to unregister.</param>
        internal void Unregister(AudioInputSystem input)
        {
            lock (_sessionLock)
            {
                int sessionId = input.GetSessionId();

                _sessions[input.GetSessionId()] = null;

                ReleaseSessionId(sessionId);
            }
        }
 /// <summary>
 /// Register a new <see cref="AudioInputSystem"/>.
 /// </summary>
 /// <param name="input">The <see cref="AudioInputSystem"/> to register.</param>
 private void Register(AudioInputSystem input)
 {
     lock (_sessionLock)
     {
         _sessions[input.GetSessionId()] = input;
     }
 }