Please check whether the use of 'einstall' in this ebuild is actually needed. From a quick glance at the Makefile, it seems to have proper support for DESTDIR. Therefore, if possible please replace the call to 'einstall' with proper 'default' or 'emake DESTDIR="${D}" install'. Thanks.
Turns out it was needed in this case. commit 1c8ca3692822fe070a8aa920fd06d7398c2b2364 Author: Michael Orlitzky <mjo@gentoo.org> Date: Wed Aug 24 15:25:58 2016 -0400 media-sound/rplay: new revision with EAPI=6. The original purpose of this new revision was to fix the use of einstall reported in bug 521564. However, einstall proved necessary, so along with the update to EAPI=6 -- where einstall is banned -- I inlined its behavior. The multilib and eutils eclasses, now unused, were dropped. The latest debian patchset was also included. Package-Manager: portage-2.2.28