Intel Core i7-6700K @ 4.00GHz, 32 GB RAM
FL Studio v12.3 [build 34] 64-bit
Here's a bug which happens when re-arranging FX slots in the mixer:
1. Download and open attached FLS file.
2. Open the mixer.
3. Click the mixer's Master channel; you will notice the FX section contains two FX plugins, Fruity Delay 2 and Fruity PanOMatic. Ensure both plugins are visible.
4. Open the Playlist; you will notice it contains two automation clips, a blue one and a red one. These are lined to parameters of the FX slots on the Mixer's Master channel.
5. Ensure you are in Song mode, then click the Play button. You should see the linked parameters dance up and down as dictated by the automation clips they are linked to.
6. Now starts the fun part. Position the mouse pointer over the Fruity Delay 2 FX slot in the mixer.
7. Keep the mouse still, and turn the mouse wheel down one notch to move Fruity Delay 2 below Fruity PanOMatic.
Problem: After completing step 7, Fruity Delay 2 moves below Fruity PanOMatic (as expected), however Fruity PanOMatic > LFO AMT is no longer being automated, instead Fruity Delay 2 > VOL is now automated (even though we never explicitly instructed FL Studio to do so).
In short, the last moved FX slot "absorbs" the controller links from all the other FX slots on the same mixer channel, including the mix level knobs and mute buttons. This issue also applies to empty FX slots.
Below is an animated capture of this, here you can see how all the parameters that were being automated stop working as soon as an FX slot is moved:
