Upgraded to 18.04  from 17.10 and have no issues. Qjackctrl works fine.
(Low latency kernel). Perhpas you can reinstall QjackCtrl.4ms latency
(128 / 3 buffers  setting)  w/o any XRUNs on a Scarlett 18i20 Gen 1 USB
2.0. So far no reasons to upgrade to a Gen 2 which (probably still) has
no Alsamixer support.
On Sun, 2018-05-06 at 18:47 +0000, Esteban Viveros wrote:
  Hi list!
  I don't be able to install jackd2 in new ubuntu 18.04 LTS.
 Os pacotes a seguir têm dependências desencontradas:
  jackd2 : Depende: libreadline6 (>= 6.0) mas não é instalável
           Recomenda: jackd2-firewire mas não será instalado
 How should I proceed..?
 Thanks
 --
 
www.estebanviveros.com
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