Prosecution witness Mohammed Rafe Ansari identified the voice when a conversation between a Pakistani terrorist and his handler, taped by Indian agencies during the siege of Nariman House, was played.
The handler's voice was that of Jundal, he said.
Ansari also told the court that his and Jundal's maternal grandfathers were cousins.
His cross-examination will continue tomorrow.
A native of Beed district in Maharashtra, Jundal was deported to India from Saudi Arabia in June 2012.
During the attack, terrorists were in touch, through mobile phones, with their handlers in Pakistan.
According to the charge sheet, Jundal, who was under police's scanner, fled to Bangladesh in May 2006 and from there on to Pakistan with the help of the ISI.