Be also aware that HDP files that are created with the main wav file during the bouncing process do contain the name and path of the VIP from which they originate. If these original HDP files are destroyed and automatically recreated you will not notice any difference until the moment you realize you are no more able to connect back to the original VIP using the "Edit Root VIP" function... This can be a pity in case you need to easily recall some time later the original VIPs for further edits - when creating a CD for example.
I've finally found a solution to this annoying problem, which occurs when the file analysed by Melodyne is not mono: - Open the mixing console and select the channel strip featuring Melodyne - Make the channel temporary "MONO" by ticking the 'Mono' attribute in the upmost element of the channel strip. When you're finished editing with Melodyne you can set back the channel to its previous state.