Acer Aspire 5052ANWMI actually belong to Acer Aspire 5050 Series. So, on the Acer website you need to enter the S/N number to locate the right product support (Manual, registration etc). Here is the original driver your will need and choose base on your operating system:
Acer Aspire 5052ANWMI Windows XP Driver (32-bit)
Audio
Realtek Audio Driver 5.10.0.5273 24.2 MB 2008/12/03
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