"And Isaac loved Esau, for the hunt was in his mouth" (Genesis 25:28): [Esau supplied him with] good cured meat for his mouth, a good cup for his mouth. "And Rebekah loves Jacob" (Genesis 25:28): whenever she heard his voice, she added love upon her love for him.
Isaac Loved Esau's Game While Rebekah Loved Jacob's Voice
Yalkut Shimoni on Torah 110:30
(בראשית כה כח) וַיֶּאֱהַב יִצְחָק אֶת עֵשָׂו כִּי צַיִד בְּפִיו, קוּפְרָא טָבָא לְפּוּמֵיהּ כָּסָא טָבָא לְפּוּמֵיהּ וְרִבְקָה אֹהֶבֶת אֶת יַעֲקֹב כָּל שֶׁשּׁוֹמַעַת קוֹלוֹ מוֹסֶפֶת אַהֲבָה עַל אַהֲבָתוֹ.