SEDGE WARBLER
I am in the realm of the small brown bird with this little one, so I could be mistaken but I think this is a sedge warbler. They have a white or off-white eye stripe called a supercilium which is what leads me to think it is a sedge warbler. Their backs and top of the head are dark streaked, with their heads being darker on the sides. Their chests are a buff colour which fades to a white underside.
The sedge warbler is a wetland bird preferring reedbeds, although it can occasionally be found in hedges near to water and drier places with thick, vertically stemmed growth. It likes to forage through the reeds for small insects, spiders and a few seeds. It keeps a hunched over appearance whilst foraging, almost horizontal and keeps its head tucked in, giving the illusion of having no neck. To spot this bird, you need to be near reedbeds and marshes. Livadi is probably your safest bet, although I saw this individual in the reeds on our local weir, in the South East of the island.