I'm pretty sure this subject has been covered but I have the well known 'clicks' when my loop changes 'loop points'.
in more detail, i use a 'groove' object which chops an audio loop into 16 smaller pieces. In order to succed that i calculate the total duration of the audio sample and then devide this value by 16. Then the start and end points are changing accordingly to the value 'totalduration / 16'. However, when the loop points move I get audio clicks (mainly with bass loops,etc. with drumloops sounds ok for obvius reasons).
any ideas/techniques are used in these situations?