Speex dev - Apr 2007 - Problem with speex

Hello!

I am downloaded last version of speex library and did compile DLL.

But I am have not good sound : Please see my code (Delphi) and say me  
please WHat I am do not right.
Or please send me correct compiled DLL and example of correct using  
SPEEX_MODEID_WB and SPEEX_MODEID_UWB , denoise, and other effects.

How I can set MONO mode in decode?

My Code:

smpRt:=32000;
n:=10;

   encbits: TSpeexBits;
   encstate: Pointer;
   encframe: integer;

   decbits: TSpeexBits;
   decstate: Pointer;
   decframe: integer;

   buffEnc: array of single;

   buffDec: array of single;


encstate := speex_encoder_init(speex_lib_get_mode(SPEEX_MODEID_WB));
speex_encoder_ctl(encstate,SPEEX_SET_SAMPLING_RATE,@smpRt);
speex_encoder_ctl(encstate,SPEEX_SET_QUALITY,@n);
speex_encoder_ctl(encstate,SPEEX_GET_FRAME_SIZE,@encframe);
speex_bits_init(@encbits);
SetLength(buffEnc,encframe);
enh:=0;
speex_bits_init(@decbits);
decstate := speex_decoder_init(speex_lib_get_mode(SPEEX_MODEID_WB));
speex_decoder_ctl(decstate,SPEEX_GET_FRAME_SIZE,@decframe);
speex_decoder_ctl(decstate,SPEEX_SET_ENH,@enh);
SetLength(buffDec,decframe);


Encode:
s3:string;
     for j:=0 to encframe-1 do
      buffenc[j]:=RecordBuff[j];
     speex_bits_reset(@encbits);
     speex_encode(encstate,@buffenc[0],@encbits);
     sz := speex_bits_nbytes(@encbits);
     SetLength(buffBytes,sz);
     speex_bits_write(@encbits,@buffBytes[0],sz);
     setlength(s3,length(buffbytes));
     CopyMemory(@s3[1],@buffbytes[0],length(buffbytes));

Decode:
  d:array  of smallint;


     speex_bits_read_from(@decbits,@s3[1],length(s3));
     speex_decode(decstate,@decbits,@buffdec[0]);
     setlength(d,length(buffdec));
     for j:=0 to length(buffdec)-1 do
      d[j]:=Round(buffdec[j]);


I hope you will help me.
Regards,
Paul

P.S. May be you have links to sites with examples of use speex - please  
send me.