Okay, attached N900 to laptop running Ubuntu 10.10, chose PC Suite Mode, started app, chose Stanton SCS.3D (generic engine) and UDP[5004} in settings, fired up Mixxx 1.9, loaded preset map for Stanton SCS.3D, loaded tracks onto both decks, hit play on the N900 and nothing happened.

What am I doing wrong?

barrieluv@HAL9000:~$ mixxx
Debug: [Main]: Mixxx "" is starting...
Debug: [Main]: Qt version is: 4.7.0
Debug: [Main]: Configuration file is at the current version 1.9.0
Debug: [Main]: ControlObject::getControl returning NULL for ( "[Channel1]" , "volume" )
Debug: [Main]: ControlObject::getControl returning NULL for ( "[Channel2]" , "volume" )
Cannot connect to server socket err = No such file or directory
Cannot connect to server socket
jack server is not running or cannot be started
Debug: [Main]: ("QSQLITE", "QMYSQL3", "QMYSQL")
Debug: [Main]: src/library/trackcollection.cpp DB status: true
Debug: [Main]: QSqlError(-1, "", "")
Debug: [Main]: SchemaManager::upgradeToSchemaVersion already at version 8
Debug: [Main]: TrackDAO::initialize QThread(0x91e8f20, name = "Main") "qt_sql_default_connection"
Debug: [Main]: CrateDAO::initialize()
Debug: [Main]: CueDAO::initialize QThread(0x91e8f20, name = "Main") "qt_sql_default_connection"
Debug: [Main]: Created MissingTracksModel!
Debug: [Main]: Promo dir: "/usr/share/mixxx//promo/1.8.0/index.html"
Warning: [Main]: Object::connect: No such slot SamplerBank::loadSamplerBank(double) in src/samplerbank.cpp:16
Warning: [Main]: Object::connect: No such slot SamplerBank::saveSamplerBank(double) in src/samplerbank.cpp:18
Debug: [Main]: ControlObject::getControl returning NULL for ( "[ReplayGain]" , "InitialReplayGainBoost" )
Debug: [Main]: ControlObject::getControl returning NULL for ( "[Mixer Profile]" , "LoEQFrequency" )
Debug: [Main]: Setting "[Channel1]" "filterLowKill" as toggle
Debug: [Main]: Setting "[Channel1]" "filterMidKill" as toggle
Debug: [Main]: Setting "[Channel1]" "filterHighKill" as toggle
Debug: [Main]: ControlObject::getControl returning NULL for ( "[Flanger]" , "lfoDepth" )
Debug: [Main]: ControlObject::getControl returning NULL for ( "[Flanger]" , "lfoDelay" )
Debug: [Main]: ControlObject::getControl returning NULL for ( "[Flanger]" , "lfoPeriod" )
Debug: [Main]: Setting "[Channel1]" "flanger" as toggle
Debug: [Main]: Setting "[Channel1]" "play" as toggle
Debug: [Main]: Setting "[Channel1]" "repeat" as toggle
Debug: [Main]: CachingReader using 4980736 bytes.
Debug: [Main]: Setting "[Channel1]" "keylock" as toggle
Debug: [Main]: Setting "[Channel1]" "pfl" as toggle
Debug: [Main]: Setting "[Channel2]" "filterLowKill" as toggle
Debug: [Main]: Setting "[Channel2]" "filterMidKill" as toggle
Debug: [Main]: Setting "[Channel2]" "filterHighKill" as toggle
Debug: [Main]: Setting "[Channel2]" "flanger" as toggle
Debug: [Main]: Setting "[Channel2]" "play" as toggle
Debug: [Main]: Setting "[Channel2]" "repeat" as toggle
Debug: [Main]: CachingReader using 4980736 bytes.
Debug: [Main]: Setting "[Channel2]" "keylock" as toggle
Debug: [Main]: Setting "[Channel2]" "pfl" as toggle
Debug: [Main]: Constructed LibraryScanner
Debug: [Main]: iTunes Album Art path is: ""
Debug: [Main]: Could not read "/home/barrieluv/.mixxx/midi/MixxxMIDIDevices"
Debug: [Main]: MidiDeviceManager::getDeviceList
Debug: [Main]: Scanning PortMIDI devices:
Debug: [Main]: Found output device # 0 Midi Through Port-0
Debug: [Main]: Found input device # 1 Midi Through Port-0
Debug: [Main]: Linking to output device # 0 "Midi Through Port-0"
Debug: [Main]: Starting script engine with output device ""
Debug: [MidiScriptEngine 1]: MIDI Device in script engine is: ""
Debug: [Main]: MidiDeviceManager: Setting up devices
Debug: [Main]: PortMIDI device "1. Midi Through Port-0" already closed
Debug: [Main]: MidiMapping: Loading MIDI preset from "/home/barrieluv/.mixxx/midi/Midi_Through_Port-0.midi.xml"
Debug: [Main]: MidiOutputMappingTableModel::removeRows()
Debug: [Main]: "Midi Through Port-0" settings found
Debug: [MidiScriptEngine 1]: MidiScriptEngine: Loading & evaluating all MIDI script code
Debug: [MidiScriptEngine 1]: MidiScriptEngine: Loading "/usr/share/mixxx/midi/midi-mappings-scripts.js"
Debug: [MidiScriptEngine 1]: MidiScriptEngine: Loading "/usr/share/mixxx/midi/Stanton-SCS3d-scripts.js"
Debug: [Main]: MidiMapping: Input parsed!
Debug: [Main]: MidiMapping: Output parsed!
Debug: [Main]: Opening Device: "1._Midi_Through_Port-0"
Debug: [Main]: MidiMapping::applyPreset()
Debug: [MidiScriptEngine 1]: "StantonSCS3d: "1. Midi Through Port-0" on MIDI channel 1 initialized."
Debug: [Main]: MidiMapping: Processing MIDI Output Bindings for "Midi Through Port-0"
Debug: [Main]: Promo dir: "/usr/share/mixxx//promo/1.8.0/index.html"
Debug: [Main]: loadSettings: 1 0 "SlowFade"
Debug: [Main]: slotApply crossfader: 1 "SlowFade"
Debug: [Main]: BpmSchemes::readXML "/home/barrieluv/.mixxx/mixxxbpmscheme.xml"
Debug: [Main]: BPM Scheme Parse error in "/home/barrieluv/.mixxx/mixxxbpmscheme.xml"
Debug: [Main]: Doctype: ""
Debug: [Main]: "error occurred while parsing element" on line 1 , column 1
Debug: [Main]: MidiDeviceManager::getDeviceList
Debug: [Main]: MidiDeviceManager::getDeviceList
Debug: [Main]: SoundManager::setupDevices()
Debug: [Main]: Building timecode lookup tables...
Allocating 2097152 slots (8192Kb) for 20 bit timecode (Serato 2nd Ed., side A)
Debug: [Main]: Starting vinyl control xwax thread
Debug: [Main]: Building timecode lookup tables...
Allocating 2097152 slots (8192Kb) for 20 bit timecode (Serato 2nd Ed., side A)
Debug: [Main]: Starting vinyl control xwax thread
Debug: [Main]: SoundDevicePortAudio:pen() "0, HDA ATI SB: STAC92xx Analog (hw:0,0)"
Debug: [Main]: m_dSampleRate 48000
Debug: [Main]: framesPerBuffer: 512
Debug: [Main]: latency in milliseconds: 10.6667
Debug: [Main]: output channels: 2 | input channels: 0
Debug: [Main]: Opening stream with id 0
Debug: [Main]: Opened PortAudio stream successfully... starting
Debug: [Main]: Dynamically loaded PortAudio library!
Debug: [Main]: PortAudio: Started stream successfully
Debug: [Main]: iNumDevicesOpenedForOutput: 1
Debug: [Main]: iNumDevicesOpenedForInput: 0
Debug: [Main]: Legacy can parse: true
PortMidi call failed...
PortMidi: `Buffer overflow'
type ENTER...Debug: [Main]: PlaylistTableModel::setPlaylist 1
Debug: [Main]: WTrackTableView::loadTrackModel() PlaylistTableModel(0xa9415cd0)
Debug: [Main]: WTrackTableView::loadTrackModel() PrepareLibraryTableModel(0xad1fa7a0)
Debug: [Main]: MixxxLibraryFeature::activate()
Debug: [Main]: WTrackTableView::loadTrackModel() LibraryTableModel(0x9378598)
Debug: [Main]: WLibrary::switchToView "WTrackTableView"
Debug: [Main]: WSearchLineEdit::restoreSearch( "" )
Warning: [Main]: QGLContext::makeCurrent(): Cannot make invalid context current.
Debug: [Main]: createWaveformViewer()
Debug: [Main]: WaveformViewerFactory :: Creating new visual waveform
Debug: [Main]: WaveformViewerFactory :: Making new GL context.
Debug: [Main]: createWaveformViewer()
Debug: [Main]: WaveformViewerFactory :: Creating new visual waveform
Debug: [Main]: WaveformViewerFactory :: Sharing existing GL context.
Debug: [Main]: ControlObject::getControl returning NULL for ( "[Channel1]" , "hotcue_33_position" )
Debug: [Main]: ControlObject::getControl returning NULL for ( "[Channel2]" , "hotcue_33_position" )
Warning: [Main]: WPushButton for control "[Channel1],hotcue_1_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel1],hotcue_2_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel1],hotcue_3_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel1],hotcue_4_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel2],hotcue_1_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel2],hotcue_2_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel2],hotcue_3_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel2],hotcue_4_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel1],loop_enabled" is null, skipping.
Warning: [Main]: WPushButton for control "[Channel2],loop_enabled" is null, skipping.
Debug: [Main]: Displaying mixxx
Debug: [Main]: Running Mixxx
Warning: [Main]: QGLShader::link: "Fragment shader(s) linked, vertex shader(s) linked.
"
Warning: [Main]: QGLShader::link: "Fragment shader(s) linked, vertex shader(s) linked.
"
Warning: [Main]: QGLShader::link: "Fragment shader(s) linked, vertex shader(s) linked.
"
Warning: [Main]: QGLShader::link: "Fragment shader(s) linked, vertex shader(s) linked.
"
Warning: [Main]: QGLShader::link: "Fragment shader(s) linked, vertex shader(s) linked.
"
Warning: [Main]: QGLShader::link: "Fragment shader(s) linked, vertex shader(s) linked.
"
Warning: [Main]: QGLShader::link: "Fragment shader(s) linked, vertex shader(s) linked.
"
Warning: [Main]: QGLShader::link: "Fragment shader(s) linked, vertex shader(s) linked.
"
Debug: [Main]: MidiMapping: Loading MIDI preset from "/usr/share/mixxx/midi/Stanton SCS.3d.midi.xml"
Debug: [Main]: MidiOutputMappingTableModel::removeRows()
Debug: [Main]: "Stanton SCS.3d" settings found

...and then it just hangs.