[PlanetCCRMA] Confusion over JACK inputs

[flump00 at breathe.com]

Hello!
I know that this sounds like a really dumb question, but I can't seem to get 
JACK applications to realise that there is any audio coming from my line 
input.
It was working the other week, and now it has all gone crazy, but I can't 
fully remember what I have changed, nor how I got it working in the first 
place... Here is my setup:
 - I have a bass + amp going into my line-in input.
 - I am using a SBLive!
When I link up ardour to use the alsa_pcm:capture_1 and alsa_pcm:capture_2 
inputs, they don't show up on the level meter for that track.
Using Qamix, I have set up the capture source to be Line. The Line playback 
volume is at 87. I am confused regarding the Capture though, as there is a 
Capture level, and a AC97 Capture section. What is the difference? Sorry... 
a dumb question, eh? 

I am confused that I can have output coming out of my speakers with no 
latency, but applications refuse to see such input of audio. 

The other week when I recorded, there was a delay between me playing a note 
and it coming out of the speakers, obviously as it was being processed.
What is the subtle difference between the connections in JACK, and the 
patchbay? Why can't I link up individual subitems in the patchbay, only the 
parent node items? 

Anybody care to walk me through the setup, explaining each step? What inputs 
am I specifying, and does JACK use some capture setup that is different to 
the ALSA capture or something? I'm very confused.
By the way, I'm using Fedora Core 2. 

Many thanks
Rich