The recent patch applied to LinuxSampler causes it to crash Ardour 3. Could you please back that out and replace it with the one found at http://tracker.ardour.org/view.php?id=4462? The second version there, called linuxsampler-patch-3.patch, is the one you want, but it's missing a file, lv2_state.h, that belongs in the src/hostplugins/lv2 directory, and can also be found there. That patch was created by user cth103, and was derived from drobilla's original patch, and works great with Ardour 3 with no crashes. Thanks.
I should have mentioned that this is when the Ardour session being loaded was saved with anything besides a GIG file (i.e. SF2 or SFZ). Also, it seems that that patch was only a partial fix even though I had thought it was complete before. For some reason, if I use an older release (2290) with the patch I referred to, it now works with SFZ's, but still crashes with SF2's, which I thought I had tested before, but I can't get it to work now even if I go back to a prior release of Ardour, so either I didn't test the patch with SF2's like I thought I remembered doing, or something else has changed, and I don't know what it is. The current release of LinuxSampler (2294), however, crashes Ardour with both SFZ's and SF2's.
*** Bug 176 has been marked as a duplicate of this bug. ***