I've uploaded a new beta 4 of Regen which contains somewhat major sound emulation updates. I've added an option to boost PSG volume to whatever the user like since I remeber something else, someone else says something else and recordings sound something else. As such, I've been unable to find a way that fits for everyone.
Apart from that, hopefully all the reported sound problems might have been fixed in this release. So don't forget to test them out.
SSG-EG part of my YM2612 core has undergone a major overhaul. So it should be pretty much very close to the real thing now. If you want to check out yourself, here
is a recording from the real thing and here
is the test ROM to run in Regen and compare results. All credits for these both go out to Nemesis.
And I almost forgot, you can download the beta from here
And my thanks goes out to a Russian guy for reporting many sound problems but wants to remain anonymous.