chain jumping

bragawd

Hi all...
got a little problem which prolly has a quick fix... when on middle ring my chain is jumping around on the biggest and next down sprockets on the cassette.
without messin my gears up all together what can i adjust !!!!

cheers bazza

ricardo_smooth

gear cables have probably stretched a little, wind out the adjuster barrel on the shifter anti-clockwise in 1/2 turns until it stops