[chuck-users] Writing multi-channel output to a WvOut

Hey all, I haven't really even looked at this before recently (never wanted to record non-realtime, and just used Jack/Logic before), but now I'm doing stuff that lags badly in real time so I'm running ChucK in --silent. Anyway, how do you write multi-channel output to a WvOut? The UGen specs and examples aren't really clear on this, and whenever I do a dac => WvOut w => blackhole; I get single-channel audio, even when I have the dac running in stereo. Thanks a lot. Andrew