I initially reported this bug to Debian but I have been asked to report it upstream.

Distribution: Debian Testing 64-bits
Package: rhythmbox
Version: 2.97-2

Here is how to reproduce the problem:
 * Insert an audio CD.
 * Start Rhythmbox.
 * Select the first track of the CD.
 * Optionally wait for the song lookup to complete.
 * Click on the Play button. The track starts playing.
 * Click on the Play button again. The track stops playing.
 * Click on the Play button again.
   -> The track does not start playing again.

Trying to play another CD track does not work either. The only way to resume playing the CD is either to restart Rhythmbox, or start playing an MP3 file (from the hard-drive) and then switch back to the CD track.

Here is the relevant part of a 'rhythmbox --debug --no-update --no-registration' log:

[...]
(19:50:02) [0x1ba5730] [maybe_start_store_request] rb-ext-db.c:959: nothing to do
(19:50:02) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 0:72000000000(0)]
(19:50:02) [0x1ba5730] [bus_cb] rb-player-gst.c:532: playbin reached state PLAYING
(19:50:02) [0x1ba5730] [volume_changed_cb] rb-mpris-plugin.c:1183: emitting Volume change
(19:50:02) [0x1ba5730] [volume_changed_cb] rb-mpris-plugin.c:1183: emitting Volume change
(19:50:02) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 0:72000000000(0)]
(19:50:02) [0x1ba5730] [volume_changed_cb] rb-mpris-plugin.c:1183: emitting Volume change
(19:50:02) [0x1ba5730] [volume_changed_cb] rb-mpris-plugin.c:1183: emitting Volume change
(19:50:03) [0x1ba5730] [inhibit] rb-power-manager-plugin.c:160: inhibiting
(19:50:03) [0x1ba5730] [inhibit_done] rb-power-manager-plugin.c:135: inhibited, got cookie 1774228482
(19:50:03) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 163858000:72000000000(0)]
(19:50:03) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 307335000:72000000000(0)]
(19:50:03) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 467837000:72000000000(0)]
(19:50:03) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 650045000:72000000000(0)]
(19:50:03) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 854040000:72000000000(0)]
(19:50:04) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 1068564000:72000000000(0)]
(19:50:04) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 1283620000:72000000000(0)]
(19:50:04) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 1497795000:72000000000(0)]
(19:50:04) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 1709865000:72000000000(0)]
(19:50:04) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 1916938000:72000000000(0)]
(19:50:05) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 2119185000:72000000000(0)]
(19:50:05) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 2315473000:72000000000(0)]
(19:50:05) [0x1ba5730] [tick_cb] rb-shell-player.c:3622: tick: [cdda://1#/dev/sr0, 2511663000:72000000000(0)]
(19:50:05) [0x1ba5730] [rb_shell_player_cmd_play] rb-shell-player.c:2341: play!
(19:50:05) [0x1ba5730] [rb_shell_player_playpause] rb-shell-player.c:2370: doing playpause
(19:50:05) [0x1ba5730] [rb_shell_player_playpause] rb-shell-player.c:2380: pausing mm player
(19:50:05) [0x1ba5730] [start_state_change] rb-player-gst.c:381: changing state to PAUSED
(19:50:05) [0x1ba5730] [start_state_change] rb-player-gst.c:385: state change succeeded synchronously
(19:50:05) [0x1ba5730] [playing_changed_cb] rb-mpris-plugin.c:1190: emitting PlaybackStatus change
(19:50:05) [0x1ba5730] [rb_shell_player_sync_with_source] rb-shell-player.c:2947: playing source: 0x1c9e310, active entry: 0x31c1be0
(19:50:05) [0x1ba5730] [rb_shell_set_window_title] rb-shell.c:2678: setting title to "The Breeders - Buffy Main Title Theme"
(19:50:05) [0x1ba5730] [rb_shell_player_sync_buttons] rb-shell-player.c:3038: syncing with source 0x1c9e310
(19:50:05) [0x1ba5730] [bus_cb] rb-player-gst.c:532: playbin reached state PAUSED
(19:50:06) [0x1ba5730] [uninhibit] rb-power-manager-plugin.c:222: uninhibiting; cookie = 1774228482
(19:50:06) [0x1ba5730] [uninhibit_done] rb-power-manager-plugin.c:200: uninhibited
(19:50:09) [0x1ba5730] [rb_audioscrobbler_should_handshake] rb-audioscrobbler.c:840: No username set
(19:50:09) [0x1ba5730] [rb_audioscrobbler_should_handshake] rb-audioscrobbler.c:840: No username set
(19:50:16) [0x1ba5730] [rb_shell_player_cmd_play] rb-shell-player.c:2341: play!
(19:50:16) [0x1ba5730] [rb_shell_player_playpause] rb-shell-player.c:2370: doing playpause
(19:50:16) [0x1ba5730] [rb_shell_player_play] rb-shell-player.c:1717: currently parsing a playlist
(19:50:16) [0x1ba5730] [rb_shell_player_sync_with_source] rb-shell-player.c:2947: playing source: 0x1c9e310, active entry: 0x31c1be0
(19:50:16) [0x1ba5730] [rb_shell_player_sync_buttons] rb-shell-player.c:3038: syncing with source 0x1c9e310
(19:50:24) [0x1ba5730] [rb_audioscrobbler_should_handshake] rb-audioscrobbler.c:840: No username set
(19:50:24) [0x1ba5730] [rb_audioscrobbler_should_handshake] rb-audioscrobbler.c:840: No username set
[...]


-- System Information:
Debian Release: wheezy/sid
  APT prefers testing
  APT policy: (500, 'testing'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.2.0-3-amd64 (SMP w/4 CPU cores)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages rhythmbox depends on:
ii  dbus                             1.6.0-1
ii  gnome-icon-theme                 3.4.0-2
ii  gstreamer0.10-plugins-base       0.10.36-1
ii  gstreamer0.10-plugins-good       0.10.31-3
ii  gstreamer0.10-x                  0.10.36-1
ii  libatk1.0-0                      2.4.0-2
ii  libc6                            2.13-33
ii  libcairo-gobject2                1.12.2-2
ii  libcairo2                        1.12.2-2
ii  libffi5                          3.0.10-3
ii  libgdk-pixbuf2.0-0               2.26.1-1
ii  libgirepository-1.0-1            1.32.1-1
ii  libglib2.0-0                     2.32.3-1
ii  libgstreamer-plugins-base0.10-0  0.10.36-1
ii  libgstreamer0.10-0               0.10.36-1
ii  libgtk-3-0                       3.4.2-2
ii  libice6                          2:1.0.8-2
ii  libjson-glib-1.0-0               0.14.2-1
ii  libpango1.0-0                    1.30.0-1
ii  libpeas-1.0-0                    1.4.0-2
ii  librhythmbox-core6               2.97-2
ii  libsm6                           2:1.2.1-2
ii  libsoup-gnome2.4-1               2.38.1-2
ii  libsoup2.4-1                     2.38.1-2
ii  libtdb1                          1.2.10-2
ii  libtotem-plparser17              3.4.2-1
ii  libxml2                          2.8.0+dfsg1-4
ii  media-player-info                17-1
ii  rhythmbox-data                   2.97-2
ii  zlib1g                           1:1.2.7.dfsg-13

Versions of packages rhythmbox recommends:
ii  avahi-daemon                0.6.31-1
ii  gstreamer0.10-plugins-ugly  0.10.19-2+b2
ii  gstreamer0.10-pulseaudio    0.10.31-3
ii  gvfs-backends               1.12.3-1+b1
ii  notification-daemon         0.7.5-1
ii  rhythmbox-plugins           2.97-2
ii  yelp                        3.4.2-1

Versions of packages rhythmbox suggests:
pn  gnome-codec-install          <none>
ii  gnome-control-center         1:3.4.2-2
ii  gstreamer0.10-plugins-bad    0.10.23-6
ii  rhythmbox-plugin-cdrecorder  2.97-2

-- no debconf information