Ubuntu: nRF Util's "Trace" command "Failed to decode modem trace: failed to fill whole buffer (error code 100)"

[Devon W]

I am using a LattePanda 3 Delta running an Ubuntu server OS (x86) headlessly. I am using a RS-232 cable to obtain the modem trace from my custom board, which uses an nRF9160.
When I run nRF Connect for Desktop (with GUI) on my Windows machine, I am able to obtain a trace easily.

Versions:
nrfutil==7.12.0
nrfutil trace==3.0.0

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On my Ubuntu machine, the trace runs without issue (see output 1 below) UNTIL IT REACHES approx. 13KB, at which it displays an error message (see output 2 below).

Command:
sudo nrfutil trace lte --input-serialport "/dev/ttyUSB0" --output-pcapng ~/nrfutil/logs/out3.pcapng

Output 1:
Saving trace to /home/dwhite/nrfutil/logs/out3.pcapng (2768 bytes)

Output 2:
Error: Failed to decode modem trace: failed to fill whole buffer (error code 100)


I repeated this 3 times. The .pcapng file sizes were 13836 B, 13228 B, 14224 B

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I then attempted to perform a modem trace and output a raw .bin file. The same issue appeared, but the files reached approximately 125 KB each.

Command:
sudo nrfutil trace lte --input-serialport "/dev/ttyUSB0" --output-raw ~/nrfutil/logs/out3.bin

Output 1:
Saving trace to /home/dwhite/nrfutil/logs/out3.bin (15360 bytes)

Output 2:
Error: Failed to decode modem trace: failed to fill whole buffer (error code 100)


The .bin file sizes were 112640 B, 137216 B, 126976 B

Why is this happening, and how can I fix this issue?

[Devon W]

Update (no solution yet):

I ran a modem trace on my Windows machine to investigate further. After the command AT+VZWAPNE? is sent by my device, my device receives this packet:

Rcvd AT Command: +VZWAPNE: 2,"VZWADMIN","IPV4V6","LTE","Enabled"  +VZWAPNE: 3,"VZWINTERNET","IPV4V6","LTE","Enabled"  +VZWAPNE: 4,"VZWAPP","IPV4V6","LTE","Enabled"  +VZWAPNE: 6,"VZWCLASS6","IPV4V6","LTE","Enabled"  +VZWAPNE: 7,"VZWIOTTS","IPV4V6","LTE","Enabled"  +VZWAPNE:  

This packet is 269 bytes long. It also happens to be the ONLY packet that exceeds 256 bytes. The next largest packet is 255 bytes.

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Hypothesis: nRFUtil's trace program does not allocate enough memory for the buffer/variable storing incoming packets.