Preferences | Library | Crossfader

Here you set how the tracks are played and what is added to the play queue.
Play random ... when play queue is empty: when the play queue is empty and you press Play, or when the last track ends and the player asks for the next one, Guayadeque adds random music by itself instead of stopping (repeat is turned off for this). The choice to its right decides whether whole albums or single tracks are added, and the amount added is 'Tracks added each time' below, still obeying the allow and deny filters of Player Filters. It is disabled by default.
Delete played tracks from play queue removes a track from the play queue once it has been played. It is disabled by default. While it is on, 'Max played tracks kept in play queue' below is unavailable, since no played tracks are kept.
Show notifications shows a desktop notification with the cover, the track name, the length, the rating and the artist and album every time a new track starts. It is enabled by default.
Enable equalizer activates the equalizer (see Equalizer). It is enabled by default.
Enable volume and fader keeps the volume control and the crossfader in the player. Unchecking it hides both controls and takes the volume and fader processing out of the audio chain: the music then plays at full volume (adjust it in the system mixer) and the tracks are always played gapless. It is enabled by default.
With 'Select the playing track in the library' checked, the Media Library Songs panel selects and reveals the track every time the player changes the playing track. Default is disabled.
Start playing the last track autoplays the resumed track when Guayadeque opens. Restore the last position in the track resumes it from the saved offset; the two options are independent, so without autoplay the saved position applies to the first manual play instead. Both are off by default.
Select in the library the track currently playing selects and reveals the track in the library songs panel every time the player starts a new track. It is disabled by default.
Start playing the last track starts the playback automatically when Guayadeque opens, resuming the track that was playing when it was closed (see 'Save play queue on close' in General). It is disabled by default.
Restore the last position in the track resumes the restored track from the position where it was left. The two options are independent: without autoplay, the saved position is used the first time you play the track yourself. It is disabled by default.
ReplayGain mode levels the loudness of the music, using the information stored in the files by the ReplayGain scanner. It can be 'Disabled' (the default), 'Track' to level every track by itself, or 'Album' to keep the relative loudness of the tracks of an album. Guayadeque reads this information but does not write it. The PreAmp slider (-20 to +20 dB, +6 dB by default) applies an extra gain on top of it, which is useful when the levelled music sounds too quiet. Both controls are disabled while the mode is 'Disabled'. For an in-depth explanation about ReplayGain see this document online.
The Random / Smart play modes group below controls how tracks are added by the random picks and by Smart Mode.
Minimum number of tracks to play required to add new ones (4 by default, 0 to 10) is when Guayadeque starts looking for new tracks: with 4, the search is launched when only 4 tracks are left to play in the queue. Tracks added each time (3 by default, 1 to 10) is how many tracks each smart mode query or random pick adds to the queue.
Max played tracks kept in play queue (20 by default, 0 to 999) is how many played tracks stay in the queue, so you can go back to recent tracks easily.
To keep Smart Mode from repeating itself, 'Don't repeat last ... artists or ... tracks' decides how many recently suggested artists (20 by default, up to 70) and tracks (100 by default, up to 300) are excluded from the new suggestions.
Genre similarity evaluation makes Smart Mode accept only tracks of the same genre as the seed track. Tracks or seeds without genre always pass, so untagged files are still suggested. The indented Strict evaluation option (only available with the former) requires the exact same genre; when it is unchecked sub-genres also match, so "Rock" accepts "Progressive Rock". Both options are disabled by default.
To keep Smart Mode from being repetitive, the 'Don't repeat last ... artists or ... tracks' spinners set how many recently suggested artists and tracks are excluded from new suggestions (20 artists and 100 tracks by default).
With 'Genre similarity evaluation' checked, Smart Mode only accepts tracks of the same genre as the seed track. Tracks or seeds without genre always pass, so untagged files can still be suggested. The indented 'Strict evaluation' option (only enabled with the former) requires the exact same genre; when unchecked, sub-genres also match, so "Rock" accepts "Progressive Rock" for example. Both options are off by default.
Some tracks have a long silence at the end, but most players only move to the next track when the file ends. With the Silence detector group you can make Guayadeque skip that silence. 'Skip at' enables the detector and sets the silence level (from -65 to 0 dB); 'In the last ... seconds' (45 by default, 5 to 360) limits the detection to the end of the track so the quiet parts of the music are not taken for silence. The level, the length and the seconds are disabled until 'Skip at' is checked, which is the default.
Output device is the audio output Guayadeque asks GStreamer to use: 'Automatic' (the default) lets the player pick the best available one, 'GConf Defined' uses the device configured in the desktop, and 'Alsa', 'PulseAudio', 'OSS' and 'CoreAudio' force that plugin. The text field beside the list is the device itself for these four, for example hw:1,0 for Alsa or a PulseAudio sink name. For 'Other' the field takes a GStreamer pipeline instead, which is how you use a sink that is not in the list.