I've been experimenting with various bit-perfect Winamp output plugin options to use with my new Behringer UCA202 DAC.
The UCA202 will work with the default Window driver, which installs when the device is first plugged in. However, ASIO will not function with the default driver. It is necessary to install the Behringer-supplied 32 or 64 bit driver. I installed the Behringer driver, BEHRINGER_2902_WIN32_2.8.40, for my 32-bit Windows 7 installation.
At first, I tried using various ASIO Winamp plugins in conjunction with the Behringer driver. They all worked. However, one common flaw was that, on certain tracks, the first few milliseconds of the track would be cut off. Although the sound quality was superb, I was unable to find any plugin settings that solved the issue. Checking gapless or no-gapless playback made no difference. I concluded the issue was likely a driver problem, as it was common among all of the ASIO Winamp plugins. I did try ASIO4ALL, but was unable to get it to function with the UCA202.
I moved on to try a few Kernel Streaming solutions for bit-perfect Winamp output. I tried the latest out_ks363.dll plugin. This completely solved the several millisecond skip at the beginning of tracks. However a new problem emerged. Pausing playback caused the last few milliseconds of audio to play repeatedly while paused. Also, the LCD Smartie Spectrum Analyzer visualization lagged the playback significantly. Unacceptable.
I then moved onto a WASAPI solution with the latest Maiko Winamp plugin in "exclusive" mode. This also solved the skip at the beginning of some tracks. However, the stuttering-on-pause issue remained. I concluded that the driver, again, was the issue.
I finally completely uninstalled the Behringer driver and re-installed the UCA202, allowing Windows 7 to load its own native driver (no ASIO support). I tried both the Kernel Streaming and WASAPI Winamp plugins with the basic Windows 7 driver. I had partial success! The skip at the beginning of tracks was gone with the new driver. Both the Kernel Streaming and WASAPI plugins now paused without the annoying repeating audio. However the LCD Smartie Spectrum Analyzer plugin still exhibited the annoying lag with the played audio with the Kernel Streaming plugin.
In the end, the only bit-perfect solution that worked satisfactorily with Winamp and the Behringer UCA202 was the Maiko WASAPI Winamp plugin running in "exclusive" mode in conjunction with the native Windows 7 UCA202 driver.
I hope this saves someone from all the thrashing about I needed to do to find a good bit-perfect solution for Winamp and the Behringer UCA202 DAC.