currently using Yokohama DNA dB ES501......the nails were embedded deep in the tyre.....
that wheel seems flater than the other 3 but not to extent of totally flat.....I drove for >1wk without realising it until the sound became obvious....then I went round the car to check....
my experience with Yoko tyres seems that it pick up nails or stones easily......last time used Yoko Aspec also same..1 nail embedded in 1 of the tyre....but using BS GR80 no such problem....
maybe becos of Yoko tyres tends to have 4 straight grooves...just my observation