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I'm running a system with Ubuntu 10.10 (pretty old, I know, but it has to be that one), with all its packages updated to the latest version supported (the distribution is not supported anymore so, to say so, "I've got the lastest Ubuntu 10.10 available")

I have a very strange issue with a USB Modem: After a few hours (I would say 5 or 6) or working properly, it stops working. Silently.

I have a program, written in Python that listens and sends commands to said modem using "pyserial" (I believe it's pyserial version 2.3 for what I read in /usr/share/pyshared/serial/__init__.py)

Everything works fine for some hours but then the modem stops sending/receving things. It doesn't throw an error, it doesn't say anything is wrong... it just stops working.

I have no clue of what may be going on so my only guess at this point is something related to the ACPI or some kind of power saver mode kicking in. I've tried to disable anything that could remotely sound to "power saving" but still fails.

Is there any way of knowing what is going on with my USB / serial port in the logs? I've checked /var/log/pm_powersave.log, syslog, dmseg but I don't really know what am I looking for (or where for that matter).

Any idea will be appreciated.

Thank you in advance.

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