Rockbox

I confirm the issue.

I checked a bit how was the keymapping on other targets like H320 or Fuze+ and adapt it to R0. I can’t say I really understood what I did exactly but I confirm it works properly now.
I can’t write a proper patch myself so if someone is willing to do it and push it, that would be nice :)

In keymap-ypr0.c
I replaced:

static const struct button_mapping button_context_settings[] = {

  { ACTION_SETTINGS_INC,       BUTTON_RIGHT,                  BUTTON_NONE },
  { ACTION_SETTINGS_INCREPEAT, BUTTON_RIGHT|BUTTON_REPEAT,    BUTTON_NONE },
  { ACTION_SETTINGS_DEC,       BUTTON_LEFT,                   BUTTON_NONE },
  { ACTION_SETTINGS_DECREPEAT, BUTTON_LEFT|BUTTON_REPEAT,     BUTTON_NONE },

  LAST_ITEM_IN_LIST__NEXTLIST(CONTEXT_TREE)

}; /* button_context_settings */

By:
static const struct button_mapping button_context_settings[] = {

  { ACTION_SETTINGS_INC,       BUTTON_UP,                     BUTTON_NONE },
  { ACTION_SETTINGS_INCREPEAT, BUTTON_UP|BUTTON_REPEAT,       BUTTON_NONE },
  { ACTION_SETTINGS_DEC,       BUTTON_DOWN,                   BUTTON_NONE },
  { ACTION_SETTINGS_DECREPEAT, BUTTON_DOWN|BUTTON_REPEAT,     BUTTON_NONE },

  LAST_ITEM_IN_LIST__NEXTLIST(CONTEXT_TREE)

}; /* button_context_settings */

static const struct button_mapping button_context_settings_right_is_inc[] = {

  { ACTION_SETTINGS_INC,       BUTTON_RIGHT,                  BUTTON_NONE },
  { ACTION_SETTINGS_INCREPEAT, BUTTON_RIGHT|BUTTON_REPEAT,    BUTTON_NONE },
  { ACTION_SETTINGS_DEC,       BUTTON_LEFT,                   BUTTON_NONE },
  { ACTION_SETTINGS_DECREPEAT, BUTTON_LEFT|BUTTON_REPEAT,     BUTTON_NONE },

  LAST_ITEM_IN_LIST__NEXTLIST(CONTEXT_STD)

}; /* button_context_settingsgraphical */

case CONTEXT_CUSTOM|CONTEXT_SETTINGS:

  case CONTEXT_SETTINGS_RECTRIGGER:
          return button_context_settings_right_is_inc;

I tested the behavior and I cannot reproduce the issue anymore.
This is justified by the commit at https://git.rockbox.org/?p=rockbox.git;a=commit;h=108a0f3 Therefore, it could be closed.