I've run into the following problems in trying to set up an experiment requiring vocal responses and am at a loss about what to do. I have DirectRT 2008.1.0.13 and Dell optiplex 760 computers.

The first problem is that the microphone input is not always detected, even when there's a microphone plugged in. Unplugging and re-plugging usually helps, but it seems problematic to regularly have to do that. It's more of an issue with the jack at the rear of the computer, but happens with the front jack as well. Sometimes after unplugging and re-plugging, it will say either the front or rear microphone is now the selected recording device, but that's still not always recognized by DirectRT and we have to unplug and re-plug again.

The even bigger problem though is that vocal input and RTs are not being recorded properly. When testing the voice response in DirectRT it sometimes seems to work fine for a bit, in terms of the monitoring and RT test functions, but other times it seems to pick up some weird electrical noise in the system even when there's no voice input. The blue line goes haywire and flashes like crazy and we get really short RTs of 0ms, 6ms, 17ms etc... even when there's no voice because they seem to be triggered by the weird electrical noise and those sound files just sound like static.

This seems to happen randomly. Will be fine for a few seconds or minutes, then problematic for a bit, then fine again, and go back and forth like that. Moving the sensitivity to the end helps a bit but the problem persists and then it's harder to get actual voice RTs. It seems to be a DirectRT software problem because when we test the microphones using the "sound and audio devices" hardware test in the control panel they seem work fine. We encounter the same problem on other computers of the same type, and with 2 different microphones. My IT dept has also tested another computer and sound card and the problem persists. They are convinced it's a software issue too.

Would really appreciate some help since I'm completely at a loss about what to do and really need to be able to run this and other vocal response exps with accurately recorded RTs.