I have a similar issue and I use 'Actual Size' to preview my icon, but when I do this, the exported icon is not pixel perfect as it looks on-screen in Illustrator. However, if I zoom to 'Actual Size' then toggle on/off pixel preview it shows the icon I have drawn correctly as it would be exported. AN annoying bug when creating icons having to toggle pixel preview on/off each time.
I have a similar issue and I use 'Actual Size' to preview my icon, but when I do this, the exported icon is not pixel perfect as it looks on-screen in Illustrator. However, if I zoom to 'Actual Size' then toggle on/off pixel preview it shows the icon I have drawn correctly as it would be exported. AN annoying bug when creating icons having to toggle pixel preview on/off each time.