I had been using the TASCAM US-122L A/D interface with an older version of Audacity under Windows XP. I got a new computer with Windows 10 and installed Audacity 2.3.2. Now when I try to overdub with the 122L as the playback device I get an error message “error opening recording device/ error code 9999 unanticipated host error”. I can record the first track, but not the overdub. I can overdub if I select the Realtek speakers as the playback device, but that creates too much latency to be workable.

Tim Connor

Are you using MME as the “host”? https://manual.audacityteam.org/man/device_toolbar.html

Yes. The other options are Windows Direct Sound and Windows WASAPI.

Check that the sample rate in the Windows sound control panel is the same in the playback and recording tabs, and that it matches the sample rate that you are using in Audacity (as shown in the “Project Rate” box in the lower left corner of the main interface).

That fixed it, Thanks!