(version 4.4.4 of phonon xine)
When I change to the xine backend I don't get any sound from playing a track in amarok.
I rebooted the machine before running amarok after changing the backend (not necessary but I'd just installed a new kernel)
The settings dialog will play sounds for the various tests and clementine will play audibly but there's nothing when I attempt to play a track using amarok.
Then when I click stop I get a crash
I get the following output when run with --debug (see the end of the extract for why I'm not posting a konqui traceback - would you like the output from gdb?)
Here's the end of the output:
amarok: BEGIN: void EngineController::stop(bool, bool) 
amarok:   [EngineController] slotTrackFinishedPlaying( "Previn, LSO" - "Previn Shostakovich 8" - "[Shostakovich] Symphony No 8 - Largo" , 0.00331595 ) 
amarok:   [SqlRegistryP] obtained max_allowed_packet is  "1048576" 
amarok:   [lastfm] scrobble(): refusing track "/home/robert/Music/LPs/Audio/split/Shostakovich/previn-dsch8-b-02.mp3" - played time ( 671 * 0.00331595 s) shorter than 30 s 
amarok:   BEGIN: void TimecodeObserver::stopped(qint64, qint64) 
amarok:   END__: void TimecodeObserver::stopped(qint64, qint64) [Took: 0s] 
amarok:   BEGIN: void Playlist::Actions::slotPlayingStopped(qint64, qint64) 
amarok:   END__: void Playlist::Actions::slotPlayingStopped(qint64, qint64) [Took: 0s] 
amarok:   BEGIN: void WikipediaEnginePrivate::_stopped() 
amarok:   END__: void WikipediaEnginePrivate::_stopped() [Took: 0s] 
amarok:   BEGIN: void OSDWidget::show(const QString&, const QImage&) 
amarok:   END__: void OSDWidget::show(const QString&, const QImage&) [Took: 0.02s] 
amarok: END__: void EngineController::stop(bool, bool) [Took: 0.048s] 
amarok: BEGIN: void ProgressWidget::redrawBookmarks(const QString*) 
amarok: END__: void ProgressWidget::redrawBookmarks(const QString*) [Took: 0s] 
amarok: BEGIN: virtual BookmarkTriangle::~BookmarkTriangle() 
amarok: END__: virtual BookmarkTriangle::~BookmarkTriangle() [Took: 0s] 
amarok: [LyricsEngine] no current track 
amarok: MPRIS2: Queueing up a PropertiesChanged signal 
amarok: BEGIN: void EngineController::slotNewTrackPlaying(const Phonon::MediaSource&) 
amarok:   [EngineController] Empty MediaSource (engine stop) 
amarok: END__: void EngineController::slotNewTrackPlaying(const Phonon::MediaSource&) [Took: 0s] 
amarok: BEGIN: void WikipediaEnginePrivate::_dataContainerUpdated(const QString&, const Data&) 
amarok: END__: void WikipediaEnginePrivate::_dataContainerUpdated(const QString&, const Data&) [Took: 0.002s] 
amarok: BEGIN: void WikipediaApplet::dataUpdated(const QString&, const Data&) 
amarok:   [WikipediaApplet] stopped 
amarok: END__: void WikipediaApplet::dataUpdated(const QString&, const Data&) [Took: 0s] 
amarok: [Albums] received albums is empty 
amarok: [ERROR__] [MySqlStorage] "GREPME MySQLe query failed! (1194) Table 'urls' is marked as crashed and should be repaired on SELECT DISTINCT albums.name, albums.id, albums.artist FROM  albums JOIN tracks ON tracks.album = albums.id INNER JOIN urls ON tracks.url = urls.id WHERE 1  AND urls.deviceid in (1,2,3,11,-1) AND ( 1   AND  NOT albums.name  = '' COLLATE utf8_unicode_ci   )  ORDER BY tracks.createdate DESC  LIMIT 7 OFFSET 0 ;" 
KCrash: Application 'amarok' crashing...
KCrash: Attempting to start /usr/lib/kde4/libexec/drkonqi from kdeinit
sock_file=/home/robert/.kde/socket-poulenc/kdeinit4__0
amarok: Fatal IO error: client killed
Unable to start Dr. Konqi

The scrobble line also looks strange - appears to be computing the time incorrectly - that track is 11m:11s long!

Should I run that sql statement on the db - I'm not seeing anything wrong when running with gstreamer (though I haven't inspected the output or run it with --debug) 

Reproducible: Always