> Hmm.  Is the failure of circuits due to use of the internal clamping
diodes
> due to some internal issue,

SCR latchup. The device can get hung into a high current mode and dissipate
a lot of current. It usually cures itself after power is off and it cools
down.

Series resistance to limit the current to a few mA has been safe in my
experience, but there are no hard specs available AFAIK.