Hello all. I know that Kassen already posted to the list about (what seems like) a filter instability problem in certain situations. But after a conversation with him it seemed that I hadn't conveyed the full nature of the problem clearly, so in this post will try to do that. To recap, here's some code from Kijjaz that demonstrates the problem: PulseOsc osc => BPF filter => blackhole; 20000 => filter.freq; 0.5 => filter.Q; for(int i; i < 100; i++) { <<< "osc: ", osc.last(), " filter: ", filter.last() >>>; samp => now; } The value output by the filter keeps rising. I ran into this problem while i had a similar patch connected to dac instead of to a blackhole. I was wearing headphones, but i took the usual precaution of turning my macbook volume to the lowest level above 0 before running the patch. To my alarm, the resulting screaming sound came through my headphones at top volume anyway. It turns out that when set to any of the volume gradations above 0, the screaming happens at effectively full volume on my macbook. So the point of this extra post is to emphasise that (at least for mac users) the filter screaming issue is currently quite dangerous for hearing/speakers, even if you take (imo) normal sensible precautions before running a patch.