Green’s Dictionary of Slang

ping-pong v.

[the image of ping-pong or table-tennis as not being a ‘serious’ sport]

(W.I.) to play at something, not to take one’s commitments seriously.

[UK]A. Salkey Quality of Violence (1978) 146: Brother Parkin ping-ponged his observation of the two in their battle of eyes and wondered who would give in first.