I've got the pilot episode,that also includes "Double Shock".I've noticed a flaw in Double shock on series two DVD set.
The Synchronisation (had to look this word up)is slightly out when Columbo is talking to Paris x2 Martin Landau.
But in the pilot epsiode this flaw is not their, It would seem that later production processess of the series has devloped a flaw but only in certain episodes. .

I've noticed this as well.

It is absolutely shocking that Universal either didn't check that the sound was synced properly or didn't care enough about us poor paying customers to fix it.