大乘百法明門論開宗義決 1.244

1.244

若依小乘皆有別性性唯無記等者。說依聲上音韻屈曲別生名等詮召於法。故離聲外別有自性。其性唯是無覆無記。但依聲起非是心力親發生故。聲是心力親發生故通三性也。既唯無記故唯有漏。若是無漏則善性故。

Regarding "if according to the Hīnayāna, they all have a distinct self-nature whose nature is solely indeterminate, etc.": it is explained that based on the inflections of rhythm and tone in sound, names and so forth are separately produced to designate dharmas; hence apart from sound there is a distinct self-nature. Its nature is solely unobscured and indeterminate; because it merely arises based on sound and is not directly produced by the power of the mind. Sound is directly produced by the power of the mind and therefore encompasses the three natures. Since it is solely indeterminate, it is solely contaminated; if it were uncontaminated, it would be wholesome in nature.