Fox Group Inc. and Cox Communications Corp. agreed to end a contract dispute that has prevented about 400,000 Cox cable customers from receiving the broadcaster's signal. Terms of the agreement were not disclosed. Fox cut off service to Cox in Dallas, Cleveland and Washington when so-called retransmission consent agreements in those cities expired Dec. 31. Cox had refused to accede to Fox's demand that it carry two small cable channels in exchange for retransmitting the network signal, arguing that viewers were not clamoring for those channels. But analysts say both parties were under pressure to come to an agreement, with some retailers in Dallas posting increased sales of satellite dishes to Cox subscribers who were irked about missing popular Fox shows. Fox risked a backlash from advertisers if ratings dropped on the coming NFL playoffs and Washington Redskins game. The dispute was resolved before contract expirations in other regions where Cox operates, such as Orange County.