I use FoobarCon Pro usually with Foobar2000. There's a strange issue: if I use a version earlier than 1.5 of foobar2000 I can see the covers also on the phone, if instead I use a version higher than 1.5, the covers no longer appear on phone.
Usually I use "filename.jpg", and everything was ok in previous versions than 1.5 and covers appears on phone.
But if I upgrade to 1.5 or higher, covers appears on the phone only if the name is "cover.jpg" or "front.jpg"
I have over 7000 album (cue+image) and I prefer to use the same file name also for images.