I work at a University in the U.S. with a large contingent of international students.  Most of upon recognizing someone using English as their second language will immediately start to pronounce each word separately.  We recognize our use of contractions, slang, and informal speech and change to more a formal clear speech.   We will even drop our use formal contractions (Don't to Do Not, etc).

It definitely can be confusing.  Then you through in some dialect difference and it can be confusing.  As one woman learned because she kept hearing her hosts saying take a pitcher when they meant picture.   Just ask us to slow down and we usually will. 

For instance an English learner told me she heard this:

Now isduh time foall good men twocome twoduh aid ofduh party.

When I said this:  Now is the time for all good men to come to the aid of the party

Now when she repeated it to me in Spanish this is what I heard

Ahora esel  momento daykay towdos los hombre sbuenos ahQueden enya yuda desu partido.

When she said: Ahora es el momento de que todos los hombres buenos acudan en ayuda de su partido

Because we are used to harder or sharper letters to end a word than in Spanish which ends in a lot of soft letters . We hear them and think like us you just contracting your words as well. 

So making sure you separate you words when talking to non native speakers is always good advice.