yes it might be the Rpm problem...
u can increase the rpm by ur self ...see the pics
if it doesnt help..then
need more info to sort it out...
1 - is it happens when engine is cold or hot or in both situation ?
2 - wether it stalls in D mode or in neutral also ?
3 - what is the RPM of engine when it is cold like in morning ? & RPM when engine hot...if no RPM meter
then tell me what happen to the engine speed ( by listenning ) from cold to hot ...
speed increases / decreases ???