  Quiescent black hole X-ray binaries (X-ray luminosities <1e34 erg/s) are
believed to be fed by hot accretion flows that launch compact, relativistic
jets. However, due to their low luminosities, quiescent jets have been detected
in the radio waveband from only five systems so far. Here, we present radio
observations of two quiescent black hole X-ray binaries with the Australia
Telescope Compact Array. One system, GS 1124-684, was not detected. The other
system, BW Cir, was detected over two different epochs in 2018 and 2020, for
which we also obtained quasi-simultaneous X-ray detections with Chandra and
Swift. BW Cir is now the sixth quiescent X-ray binary with a confirmed radio
jet. However, the distance to BW Cir is uncertain, and we find that BW Cir
shows different behaviour in the radio/X-ray luminosity plane depending on the
correct distance. Estimates based on its G-type subgiant donor star place BW
Cir at >25 kpc, while initial optical astrometric measurements from Gaia Data
Release 2 suggested likely distances of just a few kpc. Here, we use the most
recent measurements from Gaia Early Data Release 3 and find a distance
d=7.1(+4.8/-3.9) kpc and a potential kick velocity PKV=165(+81/-17) km/s, with
distances up to ~20 kpc possible based on its parallax and proper motion. Even
though there is now less tension between the parallax and donor-star based
distance measurements, it remains an unresolved matter, and we conclude with
suggestions on how to reconcile the two measurements.
