External speakers are not functioning on my laptop as before...way too soft. What happened?

I have 2 pairs of external speakers, and they used to work fine with my laptop, but now the sound is much too soft as compared to before (and compared to other peoples computers), and I noticed when I plug in the cord, at first, theres a point where sound is coming from both the internal speakers and external ones, and at this point, the external speakers are actually quite loud. But once the cord is inserted fully and sound only comes from the external speakers, the volume of the external speakers comes down to less than half its capacity. Any reasons for this and how can I fix it?

Thanks!

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driver is missing:
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salut !