ardour 4.6 bug re: midi playback

Speaking of Linux and the future, I've been learning Ardour (a digital audio workstation) on a Linux PC.
I had noticed Ardour was playing the first couple of MIDI notes silently in loop mode. I thought it was me but it's a known bug. There's even an .ogg video showing the error. Apparently it worked in Version 4.4 but broke in 4.6 and is still broken in 4.7, the current version.
Since I mainly work with MIDI loops playing hardware and software instruments, this is kind of disastrous. The dropped notes are only a problem on streaming/playback. If you render the loop as audio all the notes are there. But it's very frustrating at the composing stage not to hear exactly what you will be recording. I anxiously await Version 4.8 and the fixing of this bug.

On the topic of Linux and the difficulties of keeping it compatible with hardware, ports, and so forth, I was fortunate to find a PC with an internal PCI slot. This means I can do my audio with an RME Hammerfall (HDSP 9632) soundcard. Linux drivers and mixers were written to work with this card, probably 10 years (?) ago. But most PCs use PCIe (PCI Express) slots now, which won't work with that particular RME card. This post on the Ardour forum discusses the problems with the gradual dating of hardware recognized as Linux-friendly. (seablade: "in the PCI world honestly... that situation really is relatively unchanged to my knowledge, and the fact is that many manufacturers just aren't focusing on that area. USB has become a much larger area these days though, and while I won't agree Firewire audio is dead, I will say that it is certainly on it's way out at this point.")

Update: The MIDI dropped notes bug was fixed but MIDI looping is still imperfect, audio-playback-wise. When monitoring a MIDI loop running a softsynth, you get silent notes or stuck notes. There are workarounds such as slightly enlarging the loop brackets in non-grid mode, but what a pain. Also, in loop mode, using the plugin host Carla, you get audible pops at the loop point. Unacceptable. (Except this is being done by volunteers, mostly, and you can't really complain.)

Update, March 2018: On the Ardour forum, Paul says that "MIDI looping will be an area of intense focus for the 6.0 release. It is known to work incorrectly in all existing releases, at least in cases where note boundaries coincide with the loop boundaries (it does work in other situations)."