We're experiencing an intermittent temperature controlled autofocus idiosyncrasy where the final reported temperature is -274.0

11:42:38 19:42:38 ** Beginning Focus Run **
..
11:42:40 19:42:40 ...Current position: 3758
11:42:40 19:42:40 ...Current temperature: 13.9
..
11:46:38 19:46:38 Focus position = 3761 Avg HFD = 2.44 Avg FWHM = 1.72
11:46:38 19:46:38 Temperature: -274.0 Filter: Clear (slot 1)
11:46:38 19:46:38 ** AutoFocus Completed **

The initial reported temperature is correct, but by the time we're at the end of a 2-4 minute focus run (using FMx via ACPS) something has gone amiss. I thought the problem might be hardware related, eg a faulty temperature probe or use of 50 foot TCF control cable, but at this stage I've only seen the problem occur during a focus run.

We're using FMx's Acquire Star feature, running periodically from ACPS. Latest versions of all software.

Has anyone seen this and have any clues?

Paul