Partially MixBusses are not recorded

Hello again,

there is another question I would like to ask regarding recording.

I am using uTrack-X32 built into a X32 core, latest firmware on all components.
Channel 1-16 comes from AES50-A (S16, Mode1) to card out for recording.
They are also sent to X32 Mixbus 1-5 for our stage monitors, individual mixes for every box.
These Buses are sent back to the S16 and connect using XLR1-5 to the active monitors.
Vocals are sent from 3 Channels to MixBus 13 by SENDs, which is used for adding reverb unsing FX1.
Everything works fine in live mode, signals are present and meters show audio flowing through all these components.

INPUT is set to:
1-8 = AES50-A 1-8
9-16 = AES50-A 9-16
17-24 = Card 1-8
25-32 = Card 9-16

Output is set to:
1-10 MixBus 1-10
11 DIR OUT FX 1L
12 DIR OUT FX 1R
13 MixBus 13
14 MixBus 14
15 MixBus 15
16 MixBus 16

Recording (Card out) is set to:
1-8 = AES50-A 1-8
9-16 = AES50-A 9-16
17-24 = OUT 1-8
25-32 = OUT 9-16

For recording on USB stick connected to the card, I expect to receive:
tracks 1-16 = channels 1-16 from S16,
tracks 17-24 = OUT 1-8 (“meaning MixBus 1-8 configured in Output section 1-8”)
tracks 25-32 = OUT 9-16 configured above
=> that means
25 = Mixbus 9 (unused)
26 = Mixbus 10 (unused)
27 = 11 DIR OUT FX 1L (wet only)
28 =12 DIR OUT FX 1R (wet only)
29 = 13 MixBus 13 (dry sum only)
30 = 14 MixBus 14 (unused)
31 = 15 MixBus 15 (unused)
32 = 16 MixBus 16 (unused)

This is almost what I get, but tracks 17-24 are completely empty in the recording, while they should be filled with MixBus 1-5 on track 17-21 and only 22-24 should be without signal at the moment.
Monitors = Mixbus 1-5 are indicating audio signal and are actually delivering sound when we are recording, meters in behringer remote control app on mac show audio running on these channels.
(I am opening the recorded file for checkup, not playing back the tracks on console, just in case you wonder I do not route track 17-32 back to console for playback).
As 11,12,13 are recorded correctly on their respective tracks, I assume the settings are basically right.

I have just double checked, routing is exactly as stated above.
Any clue why there is no audio recorded from the MixBusses 1-5 = first 8 outs = recording track 17-24?
(Monitor channels are all set to post fader, faders are set to loud volume, and they are not muted)

Thank you very much!