"This system must be voltage sensitive. Improved connectivity seems to help"
Yup, haven't pulled the units yet to clean the multi-connections at the back of the units, but it has warmed up and the ARC no longer acts up.
As well, have you installed the better power chip? That really makes a difference in general, whether hot or cold.
89 Milano (wife's daily driver since 1989, Shankle Sport)
91 164S (my daily driver since 1994)
94 164LS (~Q) (trip Alfa since 2000)
72 Morgan 27 (water time since 1976)
previously owned since 1964:
62 Morris MiniMinor 850, 67 Austin 1275 Cooper S (Downton 3/4 race), 64 Giulia Sprint GT (1st red one made), 72 Fiat 128 Sedan, 75 Alfetta Sedan, 78 Alfetta Sedan, 78 GTV, 81 GTV6, 86 GTV6