Originally Posted by ncpl
I've just had a search through all online guides and documents, FAQ's etc.
I cannot find anything related to X-fade.
Not that this will tell you much, but ...

Originally Posted by Sooloos FAQ
How do I eliminate silence between songs during a party?
Often there is silence between songs built into the track instead of as a separate timing. This creates 2 to 4 seconds of silence, which may not be desirable in a social environment. When we import a CD, we search for the start and stop of audio and store these times. If you activate crossfade in the settings, we use these times instead of the original start and stop times, so there is no silence between songs.
and from the ControlPC Guide ...

Originally Posted by Sooloos ControlPC/Mac Guide
* Volume Leveling. The system can even out the peak level from album to album or track to track, preventing abrupt volume changes. To ensure best sound quality, Sooloos applies an intelligent volume adjustment at the start of each album or song rather than compression. Click the radio button to the left of your preferred option: Off, Song (volume adjustment from track to track), or Album (volume adjustment from album to album).

* Gain Adjustment. The master volume setting for the zone. You may find it convenient to turn this down for a zone with unusually sensitive speakers or where lower levels typically are desired.

* Crossfade. Length of the crossfade between tracks, adjustable from 0 (Off) to 10 seconds. Select the period you desire from the dropdown list.

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