Edit: After some testing, and others' reports, it appears it's a problem with anti-virus software. Just disable real-time protection while fighting Maghda, and the framerate will stabilize. It's a stop-gap, but it works.
10/25/2012 06:48 PMPosted by LokiIt can't be antivirus real-time protection, or Microsoft Security Essentials, especially if it's only started since 1.0.5... if it is then it makes me REALLY wonder what the game is doing behind the scenes during this specific arena.
Your computer's performance will diminish during the Maghda boss encounter. There is a specific sound file that is producing an error over and over, spamming the client with this error message.
Threats of violence. We take these seriously and will alert the proper authorities.
Posts containing personal information about other players. This includes physical addresses, e-mail addresses, phone numbers, and inappropriate photos and/or videos.
Harassing or discriminatory language. This will not be tolerated.