As documented in getRecordings, one recording can have multiple playback formats. In Record.php we assume that there is only one element (I'm still wondering why this doesn't crash).
<recording>
<recordID>ffbfc4cc24428694e8b53a4e144f414052431693-1530718721124</recordID>
<meetingID>c637ba21adcd0191f48f5c4bf23fab0f96ed5c18</meetingID>
<internalMeetingID>ffbfc4cc24428694e8b53a4e144f414052431693-1530718721124</internalMeetingID>
<name>Fred's Room</name>
<isBreakout>false</isBreakout>
<published>true</published>
<state>published</state>
<startTime>1530718721124</startTime>
<endTime>1530718810456</endTime>
<participants>3</participants>
<metadata>
<isBreakout>false</isBreakout>
<meetingName>Fred's Room</meetingName>
<gl-listed>false</gl-listed>
<meetingId>c637ba21adcd0191f48f5c4bf23fab0f96ed5c18</meetingId>
</metadata>
<playback>
<format>
<type>podcast</type>
<url>https://demo.bigbluebutton.org/podcast/ffbfc4cc24428694e8b53a4e144f414052431693-1530718721124/audio.ogg</url>
<processingTime>0</processingTime>
<length>0</length>
</format>
<format>
<type>presentation</type>
<url>https://demo.bigbluebutton.org/playback/presentation/2.0/playback.html?meetingId=ffbfc4cc24428694e8b53a4e144f414052431693-1530718721124</url>
<processingTime>7177</processingTime>
<length>0</length>
<preview>
<images>
<image alt="Welcome to" height="136" width="176">https://demo.bigbluebutton.org/presentation/ffbfc4cc24428694e8b53a4e144f414052431693-1530718721124/presentation/d2d9a672040fbde2a47a10bf6c37b6a4b5ae187f-1530718721134/thumbnails/thumb-1.png</image>
<image alt="(this slide left blank for use as a whiteboard)" height="136" width="176">https://demo.bigbluebutton.org/presentation/ffbfc4cc24428694e8b53a4e144f414052431693-1530718721124/presentation/d2d9a672040fbde2a47a10bf6c37b6a4b5ae187f-1530718721134/thumbnails/thumb-2.png</image>
<image alt="(this slide left blank for use as a whiteboard)" height="136" width="176">https://demo.bigbluebutton.org/presentation/ffbfc4cc24428694e8b53a4e144f414052431693-1530718721124/presentation/d2d9a672040fbde2a47a10bf6c37b6a4b5ae187f-1530718721134/thumbnails/thumb-3.png</image>
</images>
</preview>
</format>
</playback>
</recording>
As documented in getRecordings, one recording can have multiple playback formats. In Record.php we assume that there is only one element (I'm still wondering why this doesn't crash).
https://github.com/littleredbutton/bigbluebutton-api-php/blob/87c506564ce881836f4dba2307458a95dc5ed320/src/Core/Record.php#L54-L56