everything is pretty much default. I can't reproduce it either... maybe post an example image/code?
Here's an example of what it looks like. Notice the right sides of the black group image, selection and now playing images. They all have a faded stretched look, which is not intentional.
[img=http://img213.imageshack.us/img213/7968/scpl2ik.th.jpg]
Here's the code I use to generate my playlist.
Row Height: 22
Group Rows: 2
Edge Style: Grey
Background: White
Group By: %album%%discnumber%
Group Headers:
$imageabs2(%_width%,%_height%,0,0,0,0,0,0,C:\Program Files\foobar2000\images\header.png,NOKEEPASPECT)
$font(Segoe UI,9,bold glow-0-0-0 glowexpand-1,255-255-255)
$alignabs(6,6,$sub(%_width%,100),%_height%,left,)%artist%
$alignabs(6,24,$sub(%_width%,100),%_height%,left,)%album%$ifgreater(%totaldiscs%,1,' (Disc' %discnumber% of %totaldiscs%')',)
$alignabs(-10,6,%_width%,%_height%,right,)%genre%
$alignabs(-10,24,%_width%,%_height%,right,)%date%
Items:
$drawrect(0,0,230,%_height%,brushcolor-111-117-143 pencolor-null)
$ifgreater(%_itemcount%,10,$puts(artsize,220),$puts(artsize,$sub($mul(%_height%,%_itemcount%),10)))
$ifequal($mod(%_itemindex%,2),0,$drawrect(230,0,$sub(%_width%,230),%_height%,brushcolor-231-233-239 pencolor-null),)
$if(%_isplaying%,
$imageabs2(27,22,0,0,0,0,230,0,C:\Program Files\foobar2000\images\nowplayingleft.png,)
$imageabs2($sub(%_width%,259),%_height%,0,0,0,0,257,0,C:\Program Files\foobar2000\images\nowplayingmiddle.png,NOKEEPASPECT)
$imageabs2(2,22,0,0,0,0,$sub(%_width%,2),0,C:\Program Files\foobar2000\images\nowplayingright.png,)
)
$if(%_selected%,
$imageabs2(27,22,0,0,0,0,230,0,C:\Program Files\foobar2000\images\selectionleft.png,)
$imageabs2($sub(%_width%,259),%_height%,0,0,0,0,257,0,C:\Program Files\foobar2000\images\selectionmiddle.png,NOKEEPASPECT)
$imageabs2(2,22,0,0,0,0,$sub(%_width%,2),0,C:\Program Files\foobar2000\images\selectionright.png,)
)
$if($fileexists($replace(%path%,%filename_ext%,folder.*)),$imageabs2($get(artsize),$get(artsize),0,$ifequal(%_itemindex%,1,0,$sub($mul(%_height%,%_itemindex%),$sub(%_height%,-5))),,%_height%,5,$ifequal(%_itemindex%,1,5,0),$replace(%path%,%filename_ext%,folder.*),),)
$font(Segoe UI,8,,0-0-0)
$alignabs(233,0,20,%_height%,right,middle)$num(%tracknumber%,1).
$alignabs(262,0,$sub(%_width%,300),%_height%,left,middle)%title%
$alignabs(-10,0,%_width%,%_height%,right,middle) [%playback_time% / ]%length%
The code used is nothing special. The images that are being stretched are small, less than 30 pixels in width.
You should be able to reproduce it. I'm surprised no one else has this problem as well.
Here's a bit of VB.Net sample code I use for the proper tiling of an image.
Dim G As Graphics = Graphics.FromHwnd(Me.Handle)
Dim Img As Image = Image.FromFile("C:\Program Files\foobar2000\images\selectionmiddle.png")
Dim IA As New System.Drawing.Imaging.ImageAttributes
IA.SetWrapMode(Drawing2D.WrapMode.Tile)
Dim dstRect As New Rectangle(0, 20, Me.Width, Img.Height)
G.DrawImage(Img, dstRect, 0, 0, Img.Width, Img.Height, GraphicsUnit.Pixel, IA)
Img.Dispose()
G.Dispose()
So maybe you can add a TILE option to the $imageabs2() function?