I don't think there is, the internal speaker is probably wired in series with the external jacks, so that when an external is used the internal speaker doesn't work. One possibility may be the data jack on the back, its strictly a line out(volume control has no affect) but connecting a recorder up to the 1200bps(audio out) and ground may give you something to record. My PS2 keyboard connector didn't work, only had 4 wires for the 6 pins and the 1200 out was one of the wires missing. A simple splitter should give you the ability to record and listen on a headset.
Have you tried listening to the SSB sats with the 857 and the arrow yet?