I have for some time been battling an issue with my first OS Recto slant cab. Odd vibrations at some low frequencies especially when muting strings. At first I assumed it was the speakers, but that was prone with other speakers in the cab. Sometimes it will not happen and all is well. As of late, I have swapped speakers a few times (EV to V30, V30 to EV and then back again to V30). The last swap the resonant vibrations occurred at a different frequency than before. One would think there was a leak around the speaker seal or missed holes lacking any sealant. You would be surprised how much noise a small hole will make on the baffle board. I had removed the grill to investigate the new noise and to my disappointment what I feared was true, the upper baffle board was the culprit. When I first swapped the V30 to EV, the cab had an odd vibration that seemed to originate along the bottom edge of the lower baffle board. That was easily cured with some wood screws set at an angle to secure the lower section. I played for a while to find the vibration source. The center section (area between all 4 speakers) was the origin of the noise. I did fix this before with a new center post since the old one was loose. Now it seems that the upper baffle is no longer secure. The noise would immediately go away if I placed my finger on the area with a little pressure. The fix was an angled brace connecting the area in question to the center post. Note that when you add material to the internal space, the tone will change due to change in dampening of the baffle board and reduced air volume of the inner cavity. With the brace installed, noise is gone along with some of the tone character of the low end and portion of the mids but not quite a bad change. The end result was a tighter sound. When compared to the new OS Recto cab I have, the difference can be noticed but it is not much of a difference. Similar to comparing EV to V30 at moderate volume setting. The next fix if I need one will be to replace the 15 yr old cab with a new one which is my long term plan, and when that happens, I will have two cabs I can gig with and two that will remain in the studio. I am rebuilding the Egnator cab with the original Celestion 16 ohm speakers (75W Elite custom for Egnator, has larger dust cap and 35oz mag compared to the V30 with small dust cap and 50oz mag). I have not heard them though the Roadster so I am curious how they will sound. Actually I do not believe I played though the Egnator cab with the original speakers since my first thing I did with this $200 cab was change the speakers to the V30's. It actually sounds good, also does not require two people to carry it. Interesting to note, it has similar caster hardware used by Mesa.