I haven't found any combination of JPCSP and Java that keeps the BGM from stuttering/disappearing or the emulation from locking up.
With r2643 x86 and Java 6 u33 x86 I had bad graphical glitches. I switched to r2643 64bit and Java 7 u6 and the graphical glitches went away even with all JPCSP settings identical. Then I tried some of the newest builds of JPCSP from the automated buildbot and the graphical glitches came back (r2706 is buggy for instance).
For me, 99% of all the lockups (biggest issue by FAR) occur during the AI's turn. I almost never get a lockup during my control phase of battle or during the overworld/shop/crafting/dialogue scenes. Almost all the lockups that do occur during my own turn of battle are preceded by a stuttering of emulation during the preceding AI's turn. When I see that stuttering during the AI I know to restart the emulator because it is absolutely guaranteed that the next turn will lockup. Consequently I use the quit to title screen + save feature literally every 1-3 minutes of battle to keep from losing too much progress.
With r2643 x86 and Java 6 u33 x86 I had bad graphical glitches. I switched to r2643 64bit and Java 7 u6 and the graphical glitches went away even with all JPCSP settings identical. Then I tried some of the newest builds of JPCSP from the automated buildbot and the graphical glitches came back (r2706 is buggy for instance).
For me, 99% of all the lockups (biggest issue by FAR) occur during the AI's turn. I almost never get a lockup during my control phase of battle or during the overworld/shop/crafting/dialogue scenes. Almost all the lockups that do occur during my own turn of battle are preceded by a stuttering of emulation during the preceding AI's turn. When I see that stuttering during the AI I know to restart the emulator because it is absolutely guaranteed that the next turn will lockup. Consequently I use the quit to title screen + save feature literally every 1-3 minutes of battle to keep from losing too much progress.