关于声卡的说明，这段太难懂，求大神翻译。
MONITOR MIX – Blend in any amount of zero-latency signal (direct monitoring) from your inputs with
the output from your DAW. When fully in the "USB" position, you will hear only sound from your DAW.
When fully in the "DIRECT" position, you will hear only your source through M-Track's inputs.
This knob is useful during recording when dealing with the "buffer size" and "latency." The computer
takes a short amount of time to process the incoming audio before sending it back out; this time is
determined by the buffer size setting. Latency is the resulting delay between the incoming sound
(playing your instrument, singing, etc.) and outgoing sound (when you hear it in the DAW). Higher
buffer sizes result in higher latency.
If your computer is powerful enough, you may be able to set your buffer size low enough such that you
may never need direct monitoring. In this case, set the knob all the way to the "USB" position to monitor
only the audio output of your DAW.
In other cases, though, low buffer sizes can consume a lot of your computer's CPU and cause audio
glitches, so you may need to use a higher buffer setting, resulting in latency. In this case, use a higher
buffer size and turn the knob more towards the "DIRECT" position to monitor your incoming signal
without latency. When listening to the playback, turn it all the way to the "USB" position.
MONITOR MIX – Blend in any amount of zero-latency signal (direct monitoring) from your inputs with
the output from your DAW. When fully in the "USB" position, you will hear only sound from your DAW.
When fully in the "DIRECT" position, you will hear only your source through M-Track's inputs.
This knob is useful during recording when dealing with the "buffer size" and "latency." The computer
takes a short amount of time to process the incoming audio before sending it back out; this time is
determined by the buffer size setting. Latency is the resulting delay between the incoming sound
(playing your instrument, singing, etc.) and outgoing sound (when you hear it in the DAW). Higher
buffer sizes result in higher latency.
If your computer is powerful enough, you may be able to set your buffer size low enough such that you
may never need direct monitoring. In this case, set the knob all the way to the "USB" position to monitor
only the audio output of your DAW.
In other cases, though, low buffer sizes can consume a lot of your computer's CPU and cause audio
glitches, so you may need to use a higher buffer setting, resulting in latency. In this case, use a higher
buffer size and turn the knob more towards the "DIRECT" position to monitor your incoming signal
without latency. When listening to the playback, turn it all the way to the "USB" position.
