Yes, it seems both 8Player and Glider cut off the very beginning of each song (seems like less than 1/4 of a second). Also, no gapless playback. Roon supports gapless and does not cut off any music, so maybe this is an app issue or DLNA? Glider team has been very responsive, so maybe @joe28 can address this.
8Player and Glider are acting as a mediator in this scenario, informing the Poly what file should be played and where it's located on the network. The audio stream itself is not seen or processed by the DLNA app, so this may be something the Chord folks would need to look into.
I can confirm the Poly does implement the optional DLNA actions to support gapless playback, and Glider is invoking those actions, but there is still a short audible gap between tracks.
PS, I was testing this on my iPad with 8Player and switched to Glider on my iPhone, and Glider was on the same track I left off of on the iPad! Is this a DLNA feature?
The DLNA spec allows a control point to query a renderer for the currently playing track, so Glider does this on startup if the last selected renderer is still online. We're glad you like it!