4 files changed, 36 insertions, 3 deletions

diff --git a/apps/dsp.c b/apps/dsp.c
index 2113d251a1..4bf1ab92d6 100644
--- a/apps/dsp.c
+++ b/apps/dsp.c
@@ -1175,6 +1175,18 @@ static void channels_process_sound_chan_karaoke(int count, int32_t *buf[])
 }
 #endif /* DSP_HAVE_ASM_SOUND_CHAN_KARAOKE */
 
+static void channels_process_sound_chan_swap(int count, int32_t *buf[])
+{
+    int32_t *sl = buf[0], *sr = buf[1];
+
+    while (count-- > 0)
+    {
+        int32_t ch = *sl;
+        *sl++ = *sr;
+        *sr++ = ch;
+    }
+}
+
 static void dsp_set_channel_config(int value)
 {
     static const channels_process_fn_type channels_process_functions[] =
@@ -1186,6 +1198,7 @@ static void dsp_set_channel_config(int value)
         [SOUND_CHAN_MONO_LEFT]  = channels_process_sound_chan_mono_left,
         [SOUND_CHAN_MONO_RIGHT] = channels_process_sound_chan_mono_right,
         [SOUND_CHAN_KARAOKE]    = channels_process_sound_chan_karaoke,
+        [SOUND_CHAN_SWAP]       = channels_process_sound_chan_swap,
     };
 
     if ((unsigned)value >= ARRAYLEN(channels_process_functions) ||
diff --git a/apps/lang/english.lang b/apps/lang/english.lang
index 5a59473681..d3fac86448 100644
--- a/apps/lang/english.lang
+++ b/apps/lang/english.lang
@@ -12903,3 +12903,20 @@
     *: "Cancel Sleep Timer"
   </voice>
 </phrase>
+<phrase>
+  id: LANG_CHANNEL_SWAP
+  desc: in sound_settings
+  user: core
+  <source>
+    *: none
+    swcodec: "Swap channels"
+  </source>
+  <dest>
+    *: none
+    swcodec: "Swap channels"
+  </dest>
+  <voice>
+    *: none
+    swcodec: "Swap channels"
+  </voice>
+</phrase>
diff --git a/apps/settings_list.c b/apps/settings_list.c
index 521d565f3b..6602ec206a 100644
--- a/apps/settings_list.c
+++ b/apps/settings_list.c
@@ -678,11 +678,12 @@ const struct settings_list settings[] = {
 
     CHOICE_SETTING(F_SOUNDSETTING, channel_config, LANG_CHANNEL_CONFIGURATION,
                    0,"channels",
-                   "stereo,mono,custom,mono left,mono right,karaoke",
-                   sound_set_channels, 6,
+                   "stereo,mono,custom,mono left,mono right,karaoke,swap",
+                   sound_set_channels, 7,
                    ID2P(LANG_CHANNEL_STEREO), ID2P(LANG_CHANNEL_MONO),
                    ID2P(LANG_CHANNEL_CUSTOM), ID2P(LANG_CHANNEL_LEFT),
-                   ID2P(LANG_CHANNEL_RIGHT), ID2P(LANG_CHANNEL_KARAOKE)),
+                   ID2P(LANG_CHANNEL_RIGHT), ID2P(LANG_CHANNEL_KARAOKE),
+                   ID2P(LANG_CHANNEL_SWAP)),
     SOUND_SETTING(F_SOUNDSETTING, stereo_width, LANG_STEREO_WIDTH,
                   "stereo_width", SOUND_STEREO_WIDTH),
 #ifdef AUDIOHW_HAVE_DEPTH_3D
diff --git a/manual/configure_rockbox/sound_settings.tex b/manual/configure_rockbox/sound_settings.tex
index 76965d00cb..54031c5a20 100644
--- a/manual/configure_rockbox/sound_settings.tex
+++ b/manual/configure_rockbox/sound_settings.tex
@@ -169,6 +169,8 @@ change to customise your listening experience.
           to make the singer sound centrally placed, this often (but not 
           always) has the effect of removing the voice track from a song. This 
           setting also very often has other undesirable effects on the sound.
+      \item[Swap Channels]
+          Exchanges the left and right channels.          
   \end{description}
 
 \section{Stereo Width}