For the past couple of weeks, I’ve noticed that the first time I have to go into the pool for something it takes about 15 seconds to open. The window opens, but it’s empty, like when a drive comes online. 
Any returns to the pool are instant. But why is it lagging on the first opening? That never used to happend before.
Anybody? I want to know if this is a warning symptom of some bigger problem coming.
Instant here
ADK suggested that it might be the size of the file. The pool is being scanned for changes and additions. Once it has the info, it’s instant again from then on.
There may be something to that. I opened an empty template (16 MIDI and 48 audio tracks: all with no data) from a cold 1st time start of N7 and the pool opened instantly. Then when I opened the project I was working on, there was a slight lag opening the pool. But instant again from there on out.
Still, it seems odd. There’s less than 100 tracks, total. So, I don’t understand what so different about this one project. 
This is just a guess…Have you had any crashes lately? Even not so lately? A few weeks ago I noticed a lag on opening certain windows. UAD plugs started taking more time to display the interface. Windows Control Panel took longer to open. Sometimes Windows Explorer would do the same thing. I checked the Windows Experience Index but it gave me the same score I had previously.
I decided to do a check disk (error check) and it found and fixed all kinds of problems on my system drive. It took several hours but the lag is now gone and my system is back to it’s old snappy self.
I think it all started when I experienced a crash with Arturia’s Spark. Suddenly the interface wouldn’t load, it locked up Nuendo and I had to manually shut the machine down. This crash was months ago. But many of the files that were reported with bad clusters on the disk check were related to Arturia Spark.
So do the windows Error Check on your system drive and your audio drive. Worth a shot.