Issue with Izotope RX 6 (Resolve Studio 17.4)

I have RX 6 Elements VST plug-in on my system, inherited as a free download from a previous software bundle.
I only use these plug-ins on rare occasions, so I'm not very keen to buy a new RX 9 licence (approx 120€, and I'm just a hobbyist).
I have a small audio section (about 2 seconds) in a long .mkv file containing horrible clicks; when I isolate this section with two edits and apply the RX6 De-click plug-in, I have problems:
if I choose the "Multi-band (Random clicks)" algorithm, the selected audio clip becomes muted (except for a few millisecs at the end)
if I choose "Low-latency", the selected audio gets processed as expected, but the audio is slipped a fraction of a second forward (-> loss of sync with the remaining audio on the track)
Bouncing or audio caching make no improvement.

Could this be a compatibility issue between RX 6 & Resolve Studio 17.4.5 ?
Or is this combo "supposed to work" ? And perhaps this misbehaviour due to the type & duration of the source clip (2+ hours mkv/AAC) ?

Is the same behaviour of clip inside standalone RX application?

Audio plugins introduce latency in the path which will affect sync, especially the iZotope RX toolset.

Note that the RX DeClick plugin's "Multi-band (random clicks)" algorithm introduces 132575 samples (2762 ms) of delay and the "Low Latency" algorithm will introduce 4063 samples (85 ms) of delay.

Configure RX as an External Audio Process and use the DeClick module in the standalone application: Preferences > System > Audio Plugins > Setup External Audio Processes

Select the "Command Line" type to open the Audio Clip automatically in the external application.

Audio plugins introduce latency in the path which will affect sync, especially the iZotope RX toolset.

Note that the RX DeClick plugin's "Multi-band (random clicks)" algorithm introduces 132575 samples (2762 ms) of delay and the "Low Latency" algorithm will introduce 4063 samples (85 ms) of delay.

Configure RX as an External Audio Process and use the DeClick module in the standalone application: Preferences > System > Audio Plugins > Setup External Audio Processes

Select the "Command Line" type to open the Audio Clip automatically in the external application.

Thanks !
This is useful as it gives me more clues: the audio portion that gets exported (as WAV) in the RX6 Audio Editor is indeed offset by a fraction of a second...I assume this is due to the compressed nature of the source clip.
As a workaround, I tried to first Bounce then launch RX as external Audio Process: that worked OK
(Just Bouncing then adding the plug-in from within the Edit or Fairlight page seems to still cause the above issues)
Thanks !

It's not the compressed nature of the audio.... Izotope plugins are not qualified for Resolve. Applying them on a timeline or in Fairlight will not go well. The only reliable way is in Izotope's standalone interface. Fortunately, Resolve makes it easy, with the bounced track procedure.

It's not the compressed nature of the audio.... Izotope plugins are not qualified for Resolve. Applying them on a timeline or in Fairlight will not go well. The only reliable way is in Izotope's standalone interface. Fortunately, Resolve makes it easy, with the bounced track procedure.

I can't agree with that. I have never had a bad experience with iZotope plugins.
In general, there are not many plugins that are certified for Fairlight.

I not only tested it myself -- all kinds of anomalies can enter the exported files, not just sync loss -- but talked at length with Izotope about it. They don't qualify the product for Resolve, for a reason.

There maybe instances were there are no apparent anomalies after applying an Izotope plugin. But that shouldn't give you any confidence.

I not only tested it myself -- all kinds of anomalies can enter the exported files, not just sync loss -- but talked at length with Izotope about it. They don't qualify the product for Resolve, for a reason.

There maybe instances were there are no apparent anomalies after applying an Izotope plugin. But that shouldn't give you any confidence.

When a person uses a DVR, he must always be vigilant.
The DVR has made bugs even without a third-party plugin.