I've let the developer know, thanks.
In the meantime, I'm not saying this is the cause, but just a couple of things I spotted from the log:
1. You seem to have uncalibrated axes assigned to throttles, but maybe this is for a different control profile?
0:00:19.769 E/JOY: UNCALIBRATED AXIS DETECTED: BU0836X Interface (VID:7634PID:4097) Axis #0, assigned to joy_use_sbrk, has an expected min/max range of [0.000000, 4095.000000], but is calibrated for [0.221490, 0.795116]. You should recalibrate the device in the Settings menu.
0:00:19.769 E/JOY: CALIBRATION OVERRIDE: BU0836X Interface (VID:7634PID:4097) Axis #0 forced to be treated as calibrated due to a user pref.
0:00:19.769 E/JOY: UNCALIBRATED AXIS DETECTED: BU0836X Interface (VID:7634PID:4097) Axis #1, assigned to joy_use_thro4, has an expected min/max range of [0.000000, 4095.000000], but is calibrated for [0.175824, 0.787546]. You should recalibrate the device in the Settings menu.
0:00:19.769 E/JOY: CALIBRATION OVERRIDE: BU0836X Interface (VID:7634PID:4097) Axis #1 forced to be treated as calibrated due to a user pref.
0:00:19.769 E/JOY: UNCALIBRATED AXIS DETECTED: BU0836X Interface (VID:7634PID:4097) Axis #2, assigned to joy_use_thro3, has an expected min/max range of [0.000000, 4095.000000], but is calibrated for [0.143101, 0.724786]. You should recalibrate the device in the Settings menu.
0:00:19.769 E/JOY: CALIBRATION OVERRIDE: BU0836X Interface (VID:7634PID:4097) Axis #2 forced to be treated as calibrated due to a user pref.
0:00:19.769 E/JOY: UNCALIBRATED AXIS DETECTED: BU0836X Interface (VID:7634PID:4097) Axis #3, assigned to joy_use_reverse, has an expected min/max range of [0.000000, 4095.000000], but is calibrated for [0.083272, 0.715751]. You should recalibrate the device in the Settings menu.
0:00:19.769 E/JOY: CALIBRATION OVERRIDE: BU0836X Interface (VID:7634PID:4097) Axis #3 forced to be treated as calibrated due to a user pref.
0:00:19.769 E/JOY: UNCALIBRATED AXIS DETECTED: BU0836X Interface (VID:7634PID:4097) Axis #4, assigned to joy_use_thro2, has an expected min/max range of [0.000000, 4095.000000], but is calibrated for [0.159707, 0.785348]. You should recalibrate the device in the Settings menu.
0:00:19.769 E/JOY: CALIBRATION OVERRIDE: BU0836X Interface (VID:7634PID:4097) Axis #4 forced to be treated as calibrated due to a user pref.
0:00:19.769 E/JOY: UNCALIBRATED AXIS DETECTED: BU0836X Interface (VID:7634PID:4097) Axis #5, assigned to joy_use_thro1, has an expected min/max range of [0.000000, 4095.000000], but is calibrated for [0.166300, 0.770208]. You should recalibrate the device in the Settings menu.
0:00:19.769 E/JOY: CALIBRATION OVERRIDE: BU0836X Interface (VID:7634PID:4097) Axis #5 forced to be treated as calibrated due to a user pref.
2. You may want to set the control response and stability augmentation to zero (full left on the sliders), this is what the plane has been tuned for. But if this is deliberate, whatever works best for you, of course.
1:38:40.460 I/JOY: Control response for axis joy_use_ptch: 0.500000
1:38:40.460 I/JOY: Control response for axis joy_use_roll: 0.500000
1:38:40.460 I/JOY: Control response for axis joy_use_hdng: 0.500000
1:38:40.460 I/JOY: Stability augmentation for axis joy_use_ptch: 0.200236
1:38:40.460 I/JOY: Stability augmentation for axis joy_use_roll: 0.203190
1:38:40.460 I/JOY: Stability augmentation for axis joy_use_hdng: 0.197283
Thanks.