Grado Headphone Amplifier

Is anyone familiar with this headphone amplifier?

As I get ready for some overseas business travel, I have been dusting off some of my portable and travel gear, and I was disappointed to discover that my headphone amp has dropped one channel.

The RCA jack in the back appears to be loose - as it twists around and around - perhaps the sign of a broken connection. But I cant figure out how to open this thing, and I am wondering if it is worth the trouble to send back to Grado for repair?

Does anyone know how this might compare to other headphone amps? Or if I send it in, if they might be able to perform some updates? (I have had this one for many years, but have used it very rarely.)

Thanks for any thoughts - would use this with an iPod, and/or a laptop, with Sennheiser PXC 450 noise reduction headphones on airplanes.
Since the cost for repairing the unit is relatively small I would suggest getting it fixed. Grado has a 2-3 week turn around on repairs. Or you can send it into us if you are in a hurry. We are an authorized dealer. We can also do some mods or can suggest alternate amps. Are there better amps, yes, but you already own this amp so the cost to benefit ratio may not be there. It is a decision you and your wallet will need to make. Let me know if I can be of further help.
Thank You.
Drew Baird, P.E.
Moon Audio
308 Chrismill Lane
Holly Springs, NC 27540
I had the same issue with my ra-1 with a loose rca connection (still worked) Grado repaired free of charge.

Mention if they will add some glue to the existing connection to prevent it from happening again.

I do think it is a great amp and I get very good results with my Ultrasone 2500.