[LAU] Strange change of sample rate upon connecting mixing desk

Dear list, allow me to post a question here that I already sent to alsa-user, but without any response so far, thank you! ----------8<----------- Hi all, now here is one of the weirdest problems I have come across in the past years. Actually it is halting my current production even, but I am primarily interested how this error is caused (and how it can be solved): The sampling rate of my RME HDSP Card is set from "Internal 44.1k" to "Internal 48k" upon connecting a Yamaha DM1000 mixing console via usb! The console does not provide a USB audio interface, but several midi ports over USB, using the snd_usb_audio module. cat /proc/asound/cards: 0 [Intel ]: HDA-Intel - HDA Intel HDA Intel at 0xf2520000 irq 43 1 [DSP ]: H-DSP - Hammerfall DSP RME Hammerfall DSP + Multiface at 0xf0000000, irq 19 2 [DM1000 ]: USB-Audio - DM1000 Yamaha DM1000 at usb-0000:00:1d.0-1.2, full speed 29 [ThinkPadEC ]: ThinkPad EC - ThinkPad Console Audio Control ThinkPad Console Audio Control at EC reg 0x30, fw 6QHT26WW-1.07 control "Sample Clock Source Locking" gets set to [Off], and the sample rate is set to 48k as described above. The change is also reflected in the 'hdspconf' software that configures some properties of the card. cat /proc/asound/pcm does not list the DM1000: 00-00: CONEXANT Analog : CONEXANT Analog : playback 1 : capture 1 00-03: HDMI 0 : HDMI 0 : playback 1 01-00: RME Hammerfall DSP + Multiface : RME Hammerfall DSP + Multiface : playback 1 : capture 1 This is on a Debian box runnig kernel 3.2.0-4-rt-amd64 Let me add here, that upon starting any audio application using the same card under alsa can (re)set the sampling rate to the correct value. If the mixer is re-connected, after that audio application was launched, the sampling rate of the HDSP card is changed to 48k, causing an audible transposition. Can anyone imagine what causes this strange behavior? Thank you so much for all hints best, P