Using Spotify Connect causes brief drop outs in playback

Hi,

My problem is when I use Spotify Connect (choosing Volumio from the list of devices shown on the Spotify app) stutters or, rather, cuts out for a moment during play back. Sometimes it doesn’t happen until about 4’ into a track but sometimes happens on starting play back. It also varies as to how frequently this happens.
This happens on any device (Mac, PC and Android) including an Android phone which only has Spotify and Volumio installed.
Internet - newly installed fibre with speeds of a minimum 100 MPS, Raspberry Pi B+ with Hifiberrry which are plugged directly into router.
Volumio - version 3.812
Latest install of Spotify plug-in.

Having read some related issues, admittedly from a few years back, I have:
Uninstalled and reinstalled the plug-in and re-booted Volumio several times.
Closed competing resources on the device.
Cleared the Spotify cache
Increased buffer size from default of 1 to 8 mb
Changed quality to ‘very high’
Changed mixer type to ‘none’
Played with Volumio UI closed down.

One of these things (increased buffer size?) has made the incidents less frequent, but it’s still prevalent enough to spoil the listening experience.

The Bandcamp plug-in does not have any issues like this, (although if I use Airplay instead, it only plays one track then stops! ). Playing from the SD card is fine as well.

This probably sounds like a daft question but can the type of music impact this problem?

I have looked at the architecture diagram on the dev site and wondered if Jack/ALSA area that is the problem since it says these control timing and routing.

But if anyone has any other suggestions, they’d be gratefully received. BTW I’m not sure how to provide logs…

Thanks in advance !