FLV file with vp6f coding will not play

I have some FLV files with "on Vp6f codec" that will not play with flv extention BUT if i rename file to mp4 the file plays.
System info
Windows 7 ..Trying to play in a mci play window. Using perl.

I have some avi and webm files which if I do the same ie rename them to mp4 they work as well .
How do I make(configure) k-lite play all of flv(vp6f) files with out having to rename them.

P.S FFMPEg ffplay plays them okl.
p.p.s also have ffdshow intalled through Mega pac

On checking graph studio on both flv and 'mp4 rename' I notice MP3 Decoder DMO is in green. Not sure if this will help.,

Does GraphStudioNext play the files without renaming?

If not, some other codec is interfering. Please copy this information here:
Codec Tweak Tool > Generate Log

You should use "type MPEGVideo" in mciSendString. Then it should use DirectShow for playback, same as GraphStudioNext.

Fixed line 13 with the type MPEGVideo Now works for my flv and webm files.
Test Perl program with a little debuging in it.

use strict;
use Tkx;
use Win32::MultiMedia::Mci;
use Data::Dumper;

my $file = shift || 'c:\temp\a.flv';
my $info="                                                ";
my $mw = Tkx::widget->new('.');

my $vf = $mw->new_frame( -width => 352, -height => 240, -background => 'black');
$vf->g_pack;

my $mci = Win32::MultiMedia::Mci->open($file,alias=>'AVI1',type=>'MPEGVideo',
shareable => 1,
style => 'child',
#parent => hex($vf->winfo('id'))
parent => hex(Tkx::winfo('id',$vf))
);
print "20.info before play".$mci->info($info)."\n";
print Dumper($mci);
Win32::MultiMedia::Mci->SendString("play 'AVT1'");
print "22.After SendString=".$mci->info."\n";
$mci->play;
print $mci->info."\n";
Tkx::MainLoop();

To clarify for everyone who is curious, the "type" value defines which MCI driver to use. The standard available types can be found here:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\MCI32

The "MPEGVideo" value should work for any audio or video file that is playable though DirectShow.