Older Bryston 4B Question

I have a older Bryston 4B that I've got hooked up to a H/K 635 receiver for now as a pre-amp. I like the sound for the most part but I have a weird chirping click at shut down of the amp. The left channel chirps and then the right 5 seconds later. I'm also considering leaving the amp on all the time. That would solve my problem, but I'm still interested in the why the sound occurs. Especially if it is a bad thing. Thanks for any info that you guys have!
Now that you mention it, all my old Brystons (2B, 3B, 4B)chirpped, one channel at a time, when I shut them down, but only, if I recall correctly, if the preamp was still on with the volume cracked open a bit.

It would be easy to call Bryston and find out for sure, and I think you should. Especially since they have such excellent customer service and repair policies:

PHONE: 802-334-1201
FAX: 802-334-6658
Huh. O.K. then I guess it's no biggie. I'll give them a call to see if they can explain why they chirp.

Thanks for the info!
My 3B is chirping too. Dear Coolranch, did you have a chance to contact Bryston and find out why? It will be helpful if you can share the info. Thanks.