[Nut-upsuser] usbhid-ups becomes unresponsive after extended period

[Gary]

OS name and version: Ubuntu 20.04.3 LTS
NUT Version: 2.7.4 (installed via apt-get)
USB communication driver: 0.33
Subdriver: APC HID 0.96
Device: APC Back-UPS 550

The usbhid-ups driver seems to stop responding/serving data to upsd after running it for a few hours. It works initially when starting the NUT service but would stop working after a while. It would start working again for a bit if I restart it (sudo upsdrvctl start)

In my syslog, I would get these error messages once it stops working.

Feb  8 15:20:43 internal upsmon[25307]: UPS [ups1 at localhost]: connect failed: Connection failure: Connection timed out
Feb  8 15:20:43 internal upsmon[25307]: UPS ups1 at localhost is unavailable

Reading the log, the upshid-ups log stops updating after a while. For example, in this log, it would keep updating until 8282 seconds but nothing appears in the log afterwards. The command I use to capture the log is:
/usr/lib/nut/usbhid-ups -DDDDD -a ups1 > /var/log/usbhid_log 2>&1 &

Log file:
https://drive.google.com/file/d/11LwtnUoF7TweNDxMrIG8ZAxNTlzKwpy7/view?usp=sharing

The troubleshooting steps I have done include:
- Works without issue: Connecting to a different VM (but on same hardware, cable port, usb passthrough) running FreeBSD 12.3 and NUT 2.7.4.1
--- So it doesn't seem to be an issue with hardware, cable, or VM passthrough issue

The setup:
- APC Back-UPS connected via USB to USB port on machine, passthrough via ESXi to guest VM

Greatly appreciate any insights.

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