Jack-related bug in audio preferences

I noticed another little oddity in the audio preferences, which I can reproduce 100% on both Arch and Ubuntu: Make sure that Jack is running, then launch purr-data with pd-l2ork -jack. Turn on dsp, then invoke Edit/Preferences => all the dropdown lists come up empty like in this screenshot:

And on stdout it prints this:

undefined:1
gui_audio_properties(".gfxstub1dd7ba0",["JACK"],["JACK"]gui_pd_dsp 0);
                                                       ^

SyntaxError: missing ) after argument list
    at Socket.perfect_parser (/usr/lib/pd-l2ork/bin/pdgui.js:1196:44)
    at emitOne (events.js:96:13)
    at Socket.emit (events.js:188:7)
    at readableAddChunk (_stream_readable.js:172:18)
    at Socket.Readable.push (_stream_readable.js:130:10)
    at TCP.onread (net.js:542:20)

This only seems to happen when DSP is on.