(Comcast earnings article updated with new information on NBCU deal.)PHILADELPHIA ( TheStreet) -- Comcast ( CMCSA) saw an increase in revenue but a drop in earnings during the second quarter. The company was hit hard by financing costs related to its pending NBC Universal deal. For the quarter ended June 30, Comcast saw earnings fall 8.6% to $884 million, or 31 cents a share, compared with earnings of $967 million, or 33 cents a share, in the same period a year ago. Comcast operating expenses were $22 million, while financing costs related to the NBC Universal deal cost the company $37 million. Transaction costs for the quarter totaled $59 million. Comcast revenue increased 6.1% to $9.53 billion from $8.98 billion during the quarter due to a 5.1% increase in total customers to 67 million from 63.8 million. "We delivered healthy operating and financial results in the second quarter, reflecting overall customer growth, double-digit increases in high-speed Internet and voice revenue, an improving advertising market and continued momentum in business services," said Brian Roberts, chairman and CEO of Comcast. Though the number of video customers dropped 2.8%, the number of customers for Comcast's digital video grew 9.7% and the number of voice customers grew 16%. Although the 7.3% increase in the number of Internet subscribers was weaker than expected, Comcast still outperformed its telecommunications rivals. Both AT&T ( T) and Verizon ( VZ) saw subscriber losses in the second quarter.