Bought 2 so I could use one as a gift but neither of them put out a picture when plugged in via av. I can use hdmi if it helps set them up but the whole point is to use them on our older crt tvs
Upadte: bought a different AV cable from a pawn shop and it works! :) guess it's just a matter of luck on picking the right one, lol, although I can definitely that the combination I had originally did not work
The first thought is are you using a proper AV cable, which is one that has three RCA connectors, usually yellow for video and white/red, red/black or some other color combo for the audio.
You usually can plug each of the different RCA jacks into the TV's audio input, and the actual video port should have "noise" on it.
Other than that, try using HDMI and then checking the Jetstream's video output mode and make sure it's set to 480p or 480i since that's what composite video is officially supposed to be. Other modes may work, but I think it's always best to start with 480i and once you have that working, to go from there.
Some devices might only go down to 480p and it that's the lowest video mode, then use that.
Then there may be an option to select or activate the HDMI or AV port, I don't have a Jetstream, I've actually got a MiBox and it doesn't have an option to chose which video output is active, only the video display/output mode, and for my MiBox, 480p is the lowest video setting/mode that shows up.
I haven't tried using it's AV port since my CRT TV died before I got it.
Other than that I guess you might check to make sure that your Jetstream model actually has AV out.
The MiBox 3 has AV and optical audio out, coming out of the same port (3.5mm hole)
The MiBox 4 and S which look identical but they both only have an Aux audio output (3.5mm hole), with no optical audio either.
It also looks like the Jetstream doesn't come with an AV cable, so I'm guessing that you are providing your own, and even though they are supposed to follow a "standard" AV cables are sometimes known to have the RCA jacks that have the wrong colors on them.
The AV cable which should be 3.5mm TRRS and have three RCA connectors on the other end, if not then it might not be a AV cable or it might not follow the "standard" wiring for AV cables.
That's pretty much all I can think of when it comes to having AV problems with a media/streaming box.
I hope that this made sense and was helpful.
Best wishes and good luck!