I recently purchased a WinTV GO card. I've installed it correctly (which I am certain of because I can hear the audio coming in from the audio-in jack - which I'm guessing just passes straight through the card). The problem is that I cannot turn up the volume on the Tv card for the TV-in. If I turn the volume on my sound card all the way up I can bearly hear it.
I was thinking there might be some setting or program somewhere to change this. If not, I might have to try another card.

the card should be fine, all you should need to ever to is turn up the line in or mic in, depending on which input you're using - preferably line, with aumix. check the patch cable is going to the right input

Its not the OS because both Windows and LINUX can not adjust the volume. WinTV does not have a digital volume feature. Its a normal audio in and out found on electronic equipment. If you are using one of the sound card's outputs connected to the WinTV card. You may have Line-In set low. Try increasing it. You can always take the output from the WinTV card and connect it to an amplifier.

Actually, when I turn the line-in, the main volume, and the speakers all the way up is when I get just a tiny bit of sound from the TV part of the TV card. To listen to the audio coming in from the audio-in jack on the card, I don't have to do that.

I actually think the card itself has some sort of volume modifier for the TV input. I read on their website somewhere that if you don't turn up the volume on the TV tuner bar on the volume control, you won't get any sound. (That might have been for another card, but I think it applies.) I even tried it in windows - the volume program does have a TV Tuner bar - but the installation screwed up and now the bar doesn't work and it's always accessable - whether the drivers,etc. are totally uninstalled or not. In windows, their TV program can actually mute/unmute the volume on the card.

In short, I was thinking that any volume control for this sort of card under Linux would actually be able to control the volume on the card. The card also has an FM radio tuner, so maybe a program that could chanage the volume for that would work. I've only tried one such program, but the configure program wouldn't configure properly. So I couldn't even compile it.

Have you tried using aumix yet? Also, I don't know which distro you are using, but just out of sheer weirdness, you could try sndconfig. aumix solved my Hauppauge problems, because the input was on the lowest setting.

i know for a fact (being that i have one too) that there is no internal volume on a wintv go. any volume controls are simply controlling the soundcard line in.

aumix doesn't seem to do anything more than the mixer in KDE does. I think I'll have to try another card.

I have the same WinTV card. The sound works perfectly though I don't have a sound card.

Try hooking the WinTV card to an amplifier. I did.