Always forcing redirection prevents Chromoting from being useful in a local context where you have attached audio/video input and output devices on the host. These devices are inaccessible when input/output redirection are requested. E.g., I have web-cams attached to my Windows box but when I RDP in from my Linux box, they are inaccessible due to redirection being enabled. All other RDP clients allow disable of this feature (including Microsoft's own) for this and other reasons.

https://cs.chromium.org/chromium/src/remoting/host/win/rdp_client_window.cc?l=54

Specifically clients should be allowed to specify kRdpAudioModePlayOnServer. It'd be nice if there was a client option for this, but there are also group policy options which could be used. For some reason the Chromoting application also does not obey / is not forced to obey the group policy settings as described here though:

https://technet.microsoft.com/en-us/library/ee791794(v=ws.10).aspx

Without this I have to revert to using a KVM to switch to the actual machine and login directly.