I'm having difficulty getting recording to work consistently in Audacity on LDME 64-bit. Results ranged from no audio input, to recording cut-off after 1/2 second, to apparently working fine, but nothing reliable. Last night I attempted to record a 6-hour audio block: Audacity recorded for 6 hours, but the sound cut off after about 5 seconds.
System is an HP Pavilion dv4. Pulse audio is configured correctly, per this forum post. Devices are configured as (Host: ALSA, Playback: Default, Recording: hw:0,0), which seems to be the only recording setting that reliably provides audio input to Audacity. Audio hardware on this system is apparently based on an Intel chip: HDA Intel: STAC92xx. I've found various forum posts about similar problems here and elsewhere, but nothing that seems to definitively answer my problem.
I wasn't having this problem with Audacity on the initial 32-bit release of LMDE, and right now I'm not terribly persuaded that 64-bit is buying me any performance benefit on this computer, but fixing this problem would definitely my current biggest issue.