If I map the Arp's Rate to a macro and the macro goes to zero and back up again to higher values, the arp doesn't kick back-in when triggering notes (I use the computer keyboard for now). I need to turn off the arp, press a key then turn it on again. Same thing happens if I map an LFO to the rate and LFO goes to zero and then back up. Not sure it's a bug but thought I'd mention it. Needless to say I'm in love with Serum 2