Hola James,

The difference between oír and escuchar in Spanish is very similar to the English "hear" and "listen". 

When we use oír in Spanish we are referring to "perceiving the sound of something", this is very often with no intention from the speaker. But if we use "escuchar" we are then adding some "intention" to the hearing, we pay attention, we concentrate. 

So, coming back to that specific sentence:

"No podemos escuchar bien" 

This could be for example a group of people who are trying to "hear and understand" a listening exercise, or a podcast on the radio, or something that needs understanding/thinking apart from hearing it. 

If I am not wrong, the same happens with "hear" and "listen" in English, but I am not a native English speaker...

After stating this difference, I have to say that sometimes these verbs are used as interchangeable verbs when we don't  pay too much attention to what we want to convey though... so don't be surprised if you see "oir" when it should say "escuchar" or the other way around...

I hope this helped.

Saludos

Inma