First pipes should be Red for hot  Blue for cold sometimes I've seen clear pipe used if so could be wrong bore and clips not holding properly. 
Theory jubilee clips wrong size pipe ends splayed so far they can't grip so if clips correct sze may be they cannot be tighened properly. First try new jubilee clips next size down to whats on their but if deemed too small new of the size that is on there now. Try tighten first before following the rest below. if it still occurs go for below
Suggestion cut back on the pipes and splice with pipe straight connectors a new section in to fit to taps.
You may get away with 
1mt red for both taps check with store 
do all taps. 
5 clips for 4 taps  one for spare
1mt pipe. Don't forget to put the clip on before connecting to the tap 
5 pipe straight connectors  1 as spare.
                
 Bob
                
 March 2010