Telephone service provided by cable TV companies -- a relatively new service -- already generally ranks higher in customer satisfaction when compared with traditional phone service, a J. D. Powers & Associates study says.

Customer satisfaction for cable TV telephone service ranked higher in five of six regions in the U.S., the market research firm said, according to results of the Powers study as reported by the Associated Press on Wednesday.

Powers also found that customer spending on local and long-distance service increased to $52.40 a month, compared with $50.70 in last year's national survey. Powers noted that the increase took place in spite of the growth of VoIP calling plans, many of which provide free or very low-cost telephone service.

Noting that traditional phone companies continue to charge substantially more that cable TV firms for telephone service, Powers said customer satisfaction continued to decline nationally for telephone service generally.

Cox Communications ranked highest in customer satisfaction in some categories, the Powers study reported.