I rasied this topic a while back ...but no one had any ideas or responses...
Whilst in the shop where I bought the navibox .... I was watching there setup and low and behold they were recieving similar sporadic short lived responces in a similar area to myself ....
pointing this out to the boss ..... he had never noticed this ...
over the space of 30 minutes we were able to screen capture a number of events all located in an around the lontitude of the wash [uk] .......
these signals are transient and at best last one or two seconds showning in the altitude display ....these appear as single or multiple flags coincident on each other ...in one incidence five flags at various altitudes and colours were caught .
remember these were on the shop dislay ..not my own setup !
one thought was they may be to do with the ranges out in the wash .......but oddly the lower altitude responces ...should be below my horizon
though I've seen these at weekends which seems to limit the idea of military range activity as its very rare at weekends [I'm lead to believe ] ...
the boss of the shop was going to contact the distributers ....but I've not had chance to pop back in recently to find out what if anything has been said .