A bit of delay when using the new Siri female voice as a VoiceOver voice

Hey guys,
I'm not sure if it's me, or if it's happening across all devices able to run iOS 11, but I'm seeing a little bit of delay with the new siri voice as a VoiceOver voice.
If you don't get what I mean, I'll explain a little more in detail.
Basically, if you flick right or left using the Siri Female voice as your default VoiceOver voice, or as an option in the Language rotor settings, it takes about 1 or so seconds before it says what you've flicked to.
Since Alex is my main voice, when i flick, there is o delay at all. But with the Siri Female voice, there's a partially major delay.
Also, I noticed this with Nicky, who used to be the original Siri female voice, when I had my old iPad running iOS 9.3.5. But on this new one, I'm not so sure if Nicky's delay thing has been fixed or not.
Is anyone experiencing the delay?
Tunmi