BBC radio london programmes - why do my recordings end up "mono"?

[Mable Syrup]

When I download progs from BBC radio london, they appear to become smaller than the expected size and my player (Totem Movie Player 2.30.2 on Ubuntu) claims that they're mono.   They also appear as mp3.  Like this:

$ get_iplayer  --type=radio --pid=p01fjv45 --force
get_iplayer 2.83-ppa14, Copyright (C) 2008-2010 Phil Lewis
  This program comes with ABSOLUTELY NO WARRANTY; for details use --warranty.
  This is free software, and you are welcome to redistribute it under certain
  conditions; use --conditions for details.

INFO Trying to stream pid using type radio
INFO: pid found in cache
Matches:
12368:Robert Elms - With Oz Clarke, Tom Hall, Philip Pittack and Martin White, BBC London, Factual,Radio

INFO: 1 Matching Programmes
INFO: Checking existence of default version
INFO: flashaudio1 modes will be tried for version default
INFO: Trying flashaudio1 mode to record radio: Robert Elms - With Oz Clarke, Tom Hall, Philip Pittack and Martin White
INFO: File name prefix = Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default                 
RTMPDump v2.4-n78-git3a1e20c-ppa8~lucid
(c) 2010 Andrej Stepanchuk, Howard Chu, The Flvstreamer Team; license: GPL
Connecting ...
INFO: Connected...
Starting download at: 0.000 kB
104620.728 kB / 10550.90 sec
Download complete
MPlayer SVN-r1.0~rc3+svn20090426-4.4.3 (C) 2000-2009 MPlayer Team

Playing /media/DATA/recordings/Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default.partial.mp3.flv.
libavformat file format detected.
[lavf] Audio stream found, -aid 0
Core dumped ;)

Exiting... (End of file)
INFO: Recorded /media/DATA/recordings/Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default.mp3

INFO: Downloaded Thumbnail to '/media/DATA/recordings/Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default.jpg'
INFO: ID3 tagging MP3 file


$ get_iplayer  --type=radio --pid=p01fjv45 --i
get_iplayer 2.83-ppa14, Copyright (C) 2008-2010 Phil Lewis
  This program comes with ABSOLUTELY NO WARRANTY; for details use --warranty.
  This is free software, and you are welcome to redistribute it under certain
  conditions; use --conditions for details.

INFO Trying to stream pid using type radio
INFO: pid found in cache
Matches:
12368:Robert Elms - With Oz Clarke, Tom Hall, Philip Pittack and Martin White, BBC London, Factual,Radio
INFO: File name prefix = Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default                 

available:      Unknown
categories:     Factual
channel:        BBC London 94.9
desc:           Oz Clarke on his latest pocket wine book, Tom Hall talks about cities that look good in Autumn and East London's last surviving cloth merchants Philip Pittack and Martin White.
descmedium:     Oz Clarke on his latest pocket wine book, Tom Hall talks about cities that look good in Autumn and East London's last surviving cloth merchants Philip Pittack and Martin White.
descshort:      Oz Clarke on his latest wine book and East London's last surviving cloth merchants.
dir:            /media/DATA/recordings
dldate:         2013-09-08
dltime:         23:44:12
duration:       10800
durations:      default: 10800
episode:        With Oz Clarke, Tom Hall, Philip Pittack and Martin White
episodeshort:   With Oz Clarke, Tom Hall, Philip Pittack and Martin White
expiry:         2013-09-14T11:02:00Z
expiryrel:      in 5 days 12 hours
ext:            EXT
filename:       /media/DATA/recordings/Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default.EXT
filepart:       /media/DATA/recordings/Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default.partial.EXT
fileprefix:     Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default
firstbcast:     default: 2013-09-07T09:00:00+01:00
firstbcastrel:  default: 1 days 14 hours ago
index:          12368
lastbcast:      default: 2013-09-07T09:00:00+01:00
lastbcastrel:   default: 1 days 14 hours ago
longname:       Robert Elms
modes:          default: flashaudio1,rtspaudio1,wma1
modesizes:      default: flashaudio1=169MB,rtspaudio1=169MB,wma1=169MB
name:           Robert Elms
nameshort:      Robert Elms
pid:            p01fjv45
player:         http://www.bbc.co.uk/iplayer/episode/p01fjv45/Robert_Elms_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White/
thumbfile:      /media/DATA/recordings/Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default.jpg
thumbnail:      http://www.bbc.co.uk/iplayer/images/episode/p01fjv45_150_84.jpg
thumbnail1:     http://ichef.bbci.co.uk/programmeimages/episode/p01fjv45_86_48.jpg
thumbnail2:     http://ichef.bbci.co.uk/programmeimages/episode/p01fjv45_150_84.jpg
thumbnail3:     http://ichef.bbci.co.uk/programmeimages/episode/p01fjv45_178_100.jpg
thumbnail4:     http://ichef.bbci.co.uk/programmeimages/episode/p01fjv45_512_288.jpg
thumbnail5:     http://ichef.bbci.co.uk/programmeimages/episode/p01fjv45_528_297.jpg
thumbnail6:     http://ichef.bbci.co.uk/programmeimages/episode/p01fjv45_640_360.jpg
timeadded:      1 days 10 hours ago (1378555237)
title:          Robert Elms: With Oz Clarke, Tom Hall, Philip Pittack and Martin White
type:           radio
verpids:        default: p01fjv4m
version:        default
versions:       default
web:            http://www.bbc.co.uk/programmes/p01fjv45.html



$ ls -l Rob*mp3
-rwxrwxrwx 1 root root 105515008 2013-09-08 23:42 Robert_Elms_-_With_Oz_Clarke_Tom_Hall_Philip_Pittack_and_Martin_White_p01fjv45_default.mp3


Is this expected?
Is there any debugging I can do?

(And no, I don't mind if "it's simple" - just point me in the appropriate direction)