double buffering problem subsequent owner-drawn tabcontrol?

i have subsequent tabcontrol demonstrate purpose enabling double buffering, solely zero operative expected. here tabcontrol code:

class doublebufferedtabcontrol : tabcontrol
{
    open doublebufferedtabcontrol() : base()
    {
        this.doublebuffered = true;
        this.setstyle
            (
                controlstyles.userpaint |
                controlstyles.allpaintinginwmpaint |
                controlstyles.resizeredraw |
                controlstyles.optimizeddoublebuffer |
                controlstyles.supportstransparentbackcolor,
                false
            );
    }
}

this tabcontrol following set it's pull mode 'ownerdrawnfixed' i altered colours. here tradition sketch method:

    private vacant navigation_pagecontent_drawitem(object sender, drawitemeventargs e)
    {
        //structure.
        graphics g = e.graphics;
        tabcontrol t = (tabcontrol)sender;
        tabpage currentpage = t.tabpages[e.index];

        //get tide tab
        rectangle currenttabrect = t.gettabrect(e.index);

        //get final tab.
        rectangle lasttab = t.gettabrect(t.tabpages.count - 1);

        //main credentials rectangle.
        rectangle backgroundrect = new rectangle(lasttab.width, t.bounds.y - 4, t.width - (lasttab.width), t.height);

        //tab credentials rectangle.
        rectangle tabbackgroundrect = new rectangle(0, lasttab.y + lasttab.height, lasttab.width, t.bounds.height - (lasttab.y + lasttab.height));

        //set anitialiasing text.
        e.graphics.textrenderinghint = system.drawing.text.textrenderinghint.cleartypegridfit;

        //string format text.
        stringformat stringformat = new stringformat();
        stringformat.alignment = stringalignment.center;
        stringformat.linealignment = stringalignment.center;

        //fill background.
        g.fillrectangle(brushes.lightgray, backgroundrect);
        g.fillrectangle(brushes.bisque, tabbackgroundrect);

        //draw comparison tab.
        if(e.state == drawitemstate.selected)
        {
            g.fillrectangle(brushes.white, e.bounds);
            rectangle selectedtaboutline = new rectangle(e.bounds.x + 2, e.bounds.y + 2, e.bounds.width, e.bounds.height - 4);
            g.drawrectangle(new pen(brushes.lightgray, 4f), selectedtaboutline);
            g.drawstring(currentpage.text, new font("arial", 12f, fontstyle.bold, graphicsunit.point), new solidbrush(color.fromargb(70, 70, 70)), currenttabrect, stringformat);
        }
        else
        {
            g.fillrectangle(new solidbrush(color.fromargb(230, 230, 230)), e.bounds);
            g.drawstring(currentpage.text, new font("arial", 12f, fontstyle.regular, graphicsunit.point), brushes.gray, currenttabrect, stringformat);
        }

    }

all service however, control double buffered still flickers resized.

any ideas?