First of all. The buffer lenght in foobar does not have to be 2050. That can just stay at 500.
I was just talking about the latency you will get from asio. That should be at 2048.
How to check if you have bit-perfect playback?
Kinda easy. Just lower the latency ( of asio4all - not foobar, leave that at 500) to 0. Most likely it will start distorting. If it distorts you have bit-perfect playback. If not you do not have bit-perfect playback. (be sure to set your latency back to 2048 when you are done checking)
ASIO4ALL isn't true ASIO it's a driver/emulation
I'll second the "eh?". No offense, but that does not really matter to this thread in my opinion. Anyways, I am just explaining how to set up asio4all. Because as far as bit-perfect playback goes it does not really matter what you use.
The unrecoverable playback error might have to do with an input device being enabled and having no channels. Or it might have to do with the original bit depth the ogg was encoded from. (8-bit/16-bit etc) If it has to do with the latter then enable: Force WDM driver to 16-bit.
That might help.