Audacity Forum

Can anyone help me? I am recording mostly speech to a laptop using a USB input. The device on Audacity is set to USB CODEC. Recording levels are fine and fully acceptable.

Suddenly, for no apparent reason, the levels go very high, totally off the scale and stay that way. If Audacity is closed down and re-opened with the signal source untouched, the levels return to acceptable once more, but go high again after a while. This seems to happen totally at random, no specific time period, sometimes never happens at all. Listening back to the recording, the sound is very distorted and extreme noise is heard when no signal is input, ie recording source on pause etc.

I am taking an output from a PA amplifier and have eliminated that as being the cause by using a different sound source. The line output is being converted to USB using a converter, which works OK on another PC and I take as working OK since the levels return to normal by resetting the Audacity program. The problem appears to be on the laptop itself, any ideas???? I have shut down a lot of the laptops startup files to create stability, have I shut down something I shouldnt have maybe??? As a final thought, the same thing happens also with other recording software, so I know Audacity is OK on that machine.

A poor USB connection can cause the symptoms you describe.
If Audacity loses the USB signal, it will not regain it, even if the signal itself comes back, until Audacity is closed and opened again.

A few things to check:

Check that the USB plug is securely inserted in the socket and is clean. Any sign of damage to the USB cable?
Try a different USB socket.
If you are using a USB hub, the switching speed of the hub may not be fast enough to keep up with the signal coming from the amplifier, as well as everything else. Use a separate USB socket on the computer for the connection from the amplifier.

PO'L

If you have one computer that likes to change levels by itself, it could be that machine is set for "auto" something. This is very popular in the newer Windows machines used for Skype, Conferencing, and other communications services.

Open your Windows Control Panels and look for the tools for your sound card or extra tools in the Windows Sound Panel. Turn off all extra services like Echo Cancellation and Auto Volume.

Koz

Irish wrote:A poor USB connection can cause the symptoms you describe.
If Audacity loses the USB signal, it will not regain it, even if the signal itself comes back, until Audacity is closed and opened again.

A few things to check:

Check that the USB plug is securely inserted in the socket and is clean. Any sign of damage to the USB cable?
Try a different USB socket.
If you are using a USB hub, the switching speed of the hub may not be fast enough to keep up with the signal coming from the amplifier, as well as everything else. Use a separate USB socket on the computer for the connection from the amplifier.

PO'L

Thanks Irish, who told you about the USB hub, I forgot to mention I was using one.

Anyway, I have tried your suggestion, unplugged the amplifier source signal from the hub and re-located it into another USB socket on the laptop and it worked fine, a solid recording at a constant excellent level for 90 minutes.

Thanks again for that, I will keep trying it with this configuration, should it go high on the levels again I will re-post the issue on this forum.