AFMG Network Forum

Jim Mobley · Member

One of the most frequent problems reported to us is audible clicks or drop outs in the audio stream. This is particularly noticeable when using sweeps, but will affect noise stimuli as well. These drop outs are most frequently caused by excessive Deferred Procedure Call (DPC) latency. If any kernel-mode device driver in your Windows system is implemented improperly and causes excessive DPC latency, drop-outs will occur when using real-time audio or video streaming applications. For a full explanation of this effect see:

http://www.thesycon.de/deu/latency_check.shtml#background

If you hear dropouts in the audio stream, first try disabling your wireless network card. Wireless NICs are the most common offenders when it comes to excessive DPC latency. You can check your computer's DPC latency with a free tool available here:

http://www.thesycon.de/deu/latency_check.shtml

One of the changes made to the EASERA Gateway vs. the Presonus Firebox was to create a driver that could compensate for up to 20,000 microseconds of latency. You can set the latency in the Gateway using the application EASERAGatewayDiag.exe which you'll find on your computer here:

C:\Program Files\RH_PreSonus\1394AudioDriver_EASERA_GATEWAY

Note that you should always use the ASIO driver with EASERA or SysTune.