I'm a really big fan of Spark and use it quite a bit. As a beta tester, I am aware of some esoteric bugs that are difficult to explain that I won't bother listing. Here are some bugs I'm aware of that remain in 2.3.0:
Master Track Limit - There is a built in limiter on the Master track which affects making a proper drum track. Either the limiter should be removed from the Master Track or an Out1 should be added to the output section when using individual outputs. (Only thing I consider a big issue. Your kick drum is probably being affected.)
Equalizer - If you add the Equalizer to a drum, and bring down the 63Hz fader all the way (-40db), save the project, and return to the project the sound of the drum disappears to silence. There also seems to be a problem with the 32Hz fader when brought down all the way and saved.
Leslie Effect – The Leslie Rotation Speed knob is mislabeled. When the Leslie Rotation Speed knob is set to "Fast" the speed eventually stops. When the Leslie Rotation Speed knob is set to "Slow" the speed is actually fast. When it is set to "Stop," the speed is actually slow.
Distortion – The Tube Distortion type does not work at a 100% Wet setting.
Saving - “Click to choose” an image does not work when saving a preset.
REV button – In the Studio panel, if I press the REV sample button on one instrument pad and then move to another instrument pad, the REV button still remains illuminated. Visually there is no way to tell if a sample is reversed.
Vocal Filter LFO - The LFO Off/On Switch on the Vocal Filter behaves like a slider instead of a button.
Select 12 Shortcut - The Select-12 shortcut turns off both Accent Mode and Song Mode.
Tune Mode – Tune Mode cannot be played with the Sequencer Step buttons on the GUI. They can only be played with the hardware.
Tempo Knob after switching GUI – When switching from one GUI interface to another the tempo knob gets panned to a hard right at 300bpm (although the tempo itself will not be affected).
Library Panel - In FL Studio, when the Detached option is chosen while the Library Panel is open, then the Library Panel disappears.
LCD & Song Button - When pressing the Song button in the Main Panel to turn on Song mode in either the SparkLE or Spark Creative GUI Interface, the LCD displays "Step Mode 3.0" instead of "Song Mode: ON."
Drum Pads 15/16 – When Pad 15 & 16 is selected, often the third Instrument Parameter knob's assignment text will not be displayed. For example, if I load the "Alien Circuit" project and select Pad 15, the third Instrument Parameter knob shows that it is assigned to Freq Shift but not text is displayed beneath it Pad 16 shows it is assigned to BPF Cutoff, but again the text is not displayed. When the knob is adjusted a tooltip appears that displays "MUTE OFF." Also when the knob is in this state, right-clicking it does not bring up the "Enable/Disable motion" & "Edit motion" options. Most of the projects that seem to have this problem belong to the "Spark Factory," "Spark Vintage,” and some of the demo expansion packs. It's always the third Instrument Parameter knob for Pads 15 & 16 that is affected.
Effect Presets – I can overwrite the default factory Effect and Mixer Output presets. I can also delete them.
Mixer Faders – Double clicking the mixer faders bring them back to a value of -33db instead of the expected 0db.
Speark Creative Tap Tempo - If I tap out a tempo on the tempo pad in the the Spark Creative GUI, the tempo will update but the tempo knob itself does not react to the change.
Spark Creative GUI 9-16 - Instruments 9-16 do not display underneath the drum pads in Spark Creative GUI’s Main Panel. Instruments 1-8 remain on the display when switching to Instruments 9-16.
Verbose Mode – No accessible verbose mode on SparkLE GUI. Verbose Mode on Spark Creative GUI is incorrect. For example. Select 4 says “Prefs” but it actually opens the Studio Panel. Select 5 says “Studio” but it actually opens the Modular panel. If you leave Verbose Mode on in the Spark Creative GUI and return to the SparkLE, the layout of the text is poor, incorrect, and ugly.
Export Icons - In Windows, if you export a Spark kit the resulting icon has an iSpark logo. An exported iSpark kit has no icon.