what would cause volume to sudden ramp up to full?

Luckily I was close enough to shut down without any dammage, I hope.
I have a Ps audio PCA-2 preamp and the HCA-2 amp.
I was playing the CD player at the time at moderate volume.
Seems fine now...
This has happened to me when changing tracks on my Cairn CDP via the remote. The infrared code for track advance is the same code used for volume up on my Heed integrated. I've been told that quite a few high end manufacturers use similar sets of Phillips I/R codes which may be responsible for this type of havoc. I've eliminated the problem by using an RF capable remote and receiver. Try picking up an MX series URC brand remote and MRF base station... should do the trick.
A couple of times during thunderstorms while listening to a Forte F44 remote controlled preamp I was in the room while the volume ramped up all the way by itself. I chalked it up to the lightning. Other times I'd return home and mysteriously find the volume on max. Sometimes the volume motor would lock into advance mode like it had a mind of its own. Unplugging the unit would reset it. To protect the system when not in use I learned to engage the mute relay. Convenience has its consequences.
A perhaps related note: I cannot use my preamp remote (Kavent S-33) when operating my little remote indoor helicoptor...I've had the helicoptor hovering in its gyro mode while attempting to adjust the Kavent and the volume goes insane causing me to make an emergency landing for the heli. Once landed (or crashed as the case may be) it's all good. Also, the heli loses its mind in a certain spot near my gear...it hits the Squeezebox stream or something...this is the kind of thing I deal with...life is not always easy.
I dug into the PCA-2 manual and found a MAX volume setting that I have set...hopefullly the problem is fixed...called PS audio and they said this was probably not a problem with the pre amp but perhaps an isolated incident...my cat may have stepped on the volume control or perhaps there is a mischevious audio ghost in the house!!

Thanks for responses
Shoe, congradulations on owning two of PS Audio's best offerings! I have the HCA-2 and was wondering, you as a current owner if you know the difference between an HCA-2 that has a vented cabinet ( vents on the left side) and one that has a completely sealed cabinet? I have yet to figure this deal out.
What the heck 'ya doing playing Helicopter when you're supposed to be listening? Pay attention.

Dish Network has an RF remote for some receivers.....use it from the other room.

I found out my neighbor had the same remote so I had fun for a while......I could see their TV while standing on a ladder in my kitchen....So, I'd flip channels for them. Use your imagination!
It is true that the helicoptor distracts from listening, but it only flies for 10 minutes maybe (before needing recharging) so it's a sacrifice I feel I can make. I never fly it when listening to LPs as I'm afraid I'll crash it into my turntable...so there's that.
"when operating my little remote indoor helicoptor...I've had the helicoptor hovering in its gyro mode"
...while playing the soundtrack to Apocalypse Now? Awesome.