Strange "chorusy" recording artifact.

[Ryan1327]

I'm trying to record a guitar track (using vocal mic into 1/4" front jack) over a pre-recorded drum track. Consistently, 3-7 seconds into the recording, it turns into an odd, flanger/phaser effect-sounding mush (can see it happen in waveform as well). My settings are as follows:

Interface- Windows direct sound ('MME" gives same result)
Playback- speakers, realtech hi-def audio
record- microphone, realtech hi-def audio
channels- 1 (mono)

Thanks for any help

[steve]

using vocal mic into 1/4" front jack

Do you mean 1/8" jack?

Many RealTek HD Audio sound cards have "Noise Reduction" and "Echo Cancellation" effects switched on by default. You need to go into the RealTek control panel and switch all of the microphone effects off.

Even when you have done that it is unlikely that the sound quality will be brilliant as these devices are made to a price of just a few cents, but at least the weird phasing effect should stop.