Hello,
Thanks for reply.
I'm not connecting anything to the iPod's jack, just my headphones, but when plugging the cable into iPod and hardware volume buttons get deactivated.
This is the "3.5m AUX Audio Lineout USB Cable Charger"
http://www.ebay.co.uk/itm/3-5mm-Car-AUX-Audio-Lineout-USB-Cable-Charger-For-i-Po d-i-Phone-3GS-4G-BK-New-/301372427326?ss…
Its a cable that works with iPod / iPhone 3G / 4G
I am using an adapter to connect the cable sound out and headphones sound in jacks:
And it works with my iPod3G, the only problem is as soon as i plug the cable into iPod, it's volume key don't work, and i can't change music volume, and volume slider in the very OS disappears, but as soon as i plug the cable out of iPod, volume slider appears in the iTunes player, and iPod's volume buttons work again.
Thanks.