Networking Question re:DHCP

[gatormike]

I have learned much from the posts about networking, but have a basic question for which I can't seem to find an answer. I do not know much about networking, therefore excuse my ignorance.

I have an older Belkin router that attaches to a cable modem. All C4 gear attaches to an unmanaged cisco switch which attaches to the router. This router does not seem to be highly modifiable. It is very stable and gives me excellent wireless coverage. I will change if needed, but would rather not.

I have had a problem with Rhapsody making a crackling noise(even after the patch). Many posts here have recommended static IP addresses to help with this problem. I am considering this, but keep coming back to EagleMoon's suggestion to keep it simple for home networking (i.e. keep it on DHCP).

My basic question is: If I keep DHCP server on, but limit the IP pool; can I set static IP addresses outside the IP pool which the router will recognize???

Also, if this change is made, do the controllers need to be reidentified using the static IP addresses after making network changes in system manager?

As usual, I thank you for your guidance....

[EagleMoon]

You probably are looking for a second opinion but trust me on this one....

I have had a problem with Rhapsody making a crackling noise(even after the patch). Many posts here have recommended static IP addresses to help with this problem.

I don't know why people would think static versus dynamic IP address assignment would have anything to do with that problem. It almost certainly does not. Nothing works over IP until the device has an address; once it has an address there is no difference in how it works, whether it got the address via DHCP or via static configuration. Ignore that advice in this situation.

FYI, there ARE reasons you might want a static address. This isn't one of them. Furthermore, there *can* be network problems that cause DHCP issues which in turn cause you system problems, but those problems would not cause crackling on Rhapsody. They would stop things from working at all, at least for very long periods. And in those cases, the correct solution is to fix the underlying network problem, not to bypass DHCP. Using static addresses for that merely eliminates a symptom, not the problem.

My basic question is: If I keep DHCP server on, but limit the IP pool; can I set static IP addresses outside the IP pool which the router will recognize???

Yes, and this is how you should always do it; never set static addresses that are within your DHCP pool. Of course, they still have to be in the router's subnet as determined by the router's LAN IP address and subnet mask.

Also, if this change is made, do the controllers need to be reidentified using the static IP addresses after making network changes in system manager?

Outside my expertise but I don't think so. I could be wrong.

FYI, the crackling on Rhapsody could have any of several causes but it's most likely caused packet loss or temporarily large variations in network delays if the crackling is intermittent. I don't know precisely how Rhapsody is transmitted but I assume it uses RTP like VoIP and IP video. Even if it uses some other protocol, its characteristics are going to be similar to other real-time (RTP) traffic and will be affected by high jitter (delay variation) and packet loss. In private networks this is mitigated by QoS (quality of service) policies that give certain traffic higher priority; the Internet doesn't provide QoS so you are at the mercy of your other traffic and of the Internet performance in general.

If the crackling is constant, then it could still be those two things but it's equally likely to be in the analog side: amplifier channels, interconnect wiring, speaker wiring, speakers.

[rayk32]

I would think that if you are having static issues with Rhapsody over your network, you should be able to recreate this problem on multiple devices. Try connecting to Rhapsody over your network with your PC using the Rhapsody client and web interface ... you should get static or sound problems there as well if it is a network problem. Also try connecting your audio out to a set of self-powered speakers to see if you get static. If you confirm that you're getting static in all those scenarios, you know it's either a network problem or a hardware problem. Do you have any other audio sources that play through the same audio outs that Rhapsody uses, if so, do you have static on the non-Rhapsody source(s)? I'm guessing the answer is no. Next thing you should check is all your physical connections.

I agree 100% with EagleMoon, DHCP is not the culprit ... it's either network congestion, physical connections (network and audio wiring and the devices they connect to) or hardware failure.

You can define a DHCP scope that includes the addresses you want to statically assign. Your DHCP server must have the ability to exclude that particular contiguous range of IP addresses that you want to statically assign. Most DHCP servers, if not all, will let you do this.

Example:

Network - 192.168.0.0

Subnet Mask - 255.255.255.0

Scope Range - 192.168.0.1 - 192.168.0.254

Exclude - 192.168.0.128 - 192.168.0.254 (will not be assigned via DHCP)

[EagleMoon]

You can define a DHCP scope that includes the addresses you want to statically assign. Your DHCP server must have the ability to exclude that particular contiguous range of IP addresses that you want to statically assign. Most DHCP servers, if not all, will let you do this.

All excellent advice except for that point above. "Real" DHCP servers allow excluding addresses from the DHCP pool even if the fall between basic max and minimum address but I'd bet the Belkin does not. At least not with that terminology you show. I have a cheap Belkin 7234 that I use for a guest network and it only allows setting one contiguous range, no exclusions. Further the default range includes every address except for the router's own LAN address. So you really have to change the default range to something smaller -- either start at something like .100 or set the end to be something less than .254, say .200

BTW, I think you meant "*excludes*" the addresses you want to statically assign", not *includes*, right? And you wouldn't really start the scope with the .1 address because that's typically what the router takes by default. A few take .254 instead of .1 but whatever, you don't want the DHCP range to include the router address.

[gatormike]

Thanks for all of your help.

Per both of your advice I have tried the following:

Rhapsody works on my computer.

All new cat6 patch cables from modem to switch to c4 gear.

Tried audio out #2 on HC-300.

other audio media plays normal through c4 amp(radio, music streamed through HD set top box, DVD player, and pandora)

Rhapsody in any zone is full of static

Cable modem shows around 9 mb/s down and 4 mb/s up.

The static is intermittent and same with QoS on or off.

Have I ruled out an amp, wire, or interconnect problem??

Is there anything else I can do?? If Rhapsody works on my computer, but not on C4 gear, it seems like the HC-300 is the culprit as other audio works fine via amp???

Thanks again.

[EagleMoon]

Cable modem shows around 9 mb/s down and 4 mb/s up.

Have I ruled out an amp, wire, or interconnect problem??

Is there anything else I can do??

Are you saying you have actual traffic of 9/4Mbps or that that's the service level you're paying for? If actual traffic, what in the world are you doing to generate that traffic? And can you shut down all the other devices that generate that traffic so that only the Rhapsody streams are being received to see if the problem goes away?

You haven't completely ruled out other things until you swap everything from one of the consistently good sources with the C4 source. That would mean disconnecting the cables from the C4 audio out and connecting them to one of the other sources (like the DVD player) that's normally good. It's possible the input on the amp that the C4 is using is bad (or the cables connected to it); not likely, but possible. So this test of moving the C4 cables to another device will determine that.

Similarly, if you have an appropriate cable, you could connect your computer's audio out to the source input on the amp that the C4 controller's audio out is currently using.

[gatormike]

The numbers mentioned were from speedtest.net. I actually pay for 15/5. That differential seems weird to me....could it be an ISP problem?

I have tried swapping inputs on amp. No change. Will try the computer out to amp tomorrow with rhapsody.

Frustrating....but learning along the way....

[ILoveC4]

Does regular digital audio out from that controller sound this same way (static) or just rhapsody?

[EagleMoon]

The numbers mentioned were from speedtest.net. I actually pay for 15/5. That differential seems weird to me....could it be an ISP problem?

I have tried swapping inputs on amp. No change. Will try the computer out to amp tomorrow with rhapsody.

Wide differences between measured speeds and the advertised service level are common. The only exception that I've ever found is my AT&T U-Verse in Dallas; it's always been almost exactly what they advertise. The fact that your computer works okay rules out an ISP problem.

I assumed that your computer and your C4 controller connect directly into the same Cisco switch. If your controller connects via Cat-5/6 to the switch but the computer you were testing with connects wirelessly to the router, then you have another difference in the path. I seriously doubt it's the switch or it's connection to the router, but you should also confirm that by connecting your computer into the switch with Cat-5/6 and verifying that the quality is still good. If not, then you've narrowed the problem down to either the switch or the cable from it to the router. BTW, there's also some tiny possibility that its the connection between the switch and the C4 controller. So at some point, when nothing else has helped, you may want to swap out that cable and also try a different switch port, but those are low-probability causes.

I'm guessing you have a controller problem but what it might be is beyond my knowledge.

[gatormike]

You guys were right. I connected an audio source to the hc-300 input and it had the same problem coming from both outputs. I assume the audio outs are both broken on the controller. It is out of warranty. Do you think it would be worth it to get it repaired? I also could swap out my other hc-300 to run director. I think that would require just reloadimg the project and making all physical connections?.??

Other option is to keep it as is and use sonos with EV driver for rhapsody and other audio.

Appreciate your input. Thanks again for helping me.