Sky NZ transmits only on the horizontal pol.,nothing on vertical,hence no need for 2 cables to each receiver.
Speedbird,could be a number of things.I suggest you find the 'signal strength' display in the menu in each receiver ( usually a percentage with 100 being perfect) to compare all 3.
If the receivers are getting a low signal,it will be down to the splitter.Easily solved,just need an active splitter which has no signal loss as opposed to a passive type which does have a reasonable amount of loss on each output compared to the input.
Heavy rain (rain fade) will knock out all your receivers as rain attenuates the signals.Even the largest earth station antennas (13 metres) get knocked out by rain if it's heavy enough (Ku Band).
Nervous SLF offers good advice.Even professional receivers used in broadcasting costing more than 50 times those you have at home can be very flaky.They have to be 'power cycled' too (all power removed from unit and replaced).Welcome to the world of digital TV
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