Well on the normal audio it totally sounds like "le". I can't say for the slow audio as I don't have access to it.
The difference of pronunciation between "le" and "leur(s)" is the "r" sound, and also the "e" sound is a bit more open for "leur(s)". Note that the "s" at the end, if there is any, is not pronounced.
Try this to get used to the difference (don't mind the translation, it's just for the audio) :