Tech Support

All Codecs:

1.  Have you rebooted the boxes on both ends yet? This typically solves over half of all connection issues, and is a surprisingly overlooked piece of troubleshooting. Just because your box recently had a successful session, this does not have any bearing on if your next session will be successful.

2.  What about unplugging ISDN line for 30 seconds, or powering down externa;l NT1?

3.  “Underwater” audio, chirps, squeals, drop outs: these are typically caused by either data errors on the long distance connection or by errors on one of the two local connections. Reversing the dialing direction sometimes helps, but if the problem is on one of the users’ local end it may be impossible to route around this.

4.  Forcing your calls over a different long distance carrier might help if your normal carrier is having trouble. This is done by pre-fixing 1010 and a company specific three digit code, 1010 222 (MCI/Verizon business), 1010 333 (Sprint), or 1010 288 (AT&T) before the 1+(area code)+ 7 digit local number. Ex: 1010 333 1 415 646 8542 would place a call into EDnet’s tech support number over Sprint. Note: these calls may NOT connect if the LD carrier in question decides to not carry the call. AT&T typically are more restrictive than either Sprint or MCI.

Codec Specific issues:

Zephyrs and XStreams:

(both versions) L2mono128 sessions: if the far end studio complains of underwatery garbled audio, or no lock indication whatsoever, change your codec mode to anything else, say Layer 3, and then back to L2. This forces a reload of the MPEG code and often clears the transmission path. Unfortunately, a reboot of a zephyr does NOT reload the MPEG code and will not clear this issue.

(both versions) Layer 3 sessions. If your LOCK light (black units) or 1 & 2 lights over the receive meters (silver units) are flashing upon connection of the second call, double check the sample rate on both ends is matched. EDnet recommend Layer 3 discrete stereo (not joint) and a sample rate of 32kHz for time-code lock to picture work. Similarly, if you hear pitch-shifted audio, yet have a solid lock light, this is also indicative of a sample rate mismatch. Confirm both ISDN boxes are set to the same sample rate.
(black unit) if your zephyr boots up with a transmit of L3 dual, receive of L3 mono and a rate of 56/32 and will not initialize to your ISDN line, chances are the unit has reverted to its factory settings. This can happen if unit resets itself or the user “cold boots” the unit (Help, then *, then #), in which case you'll need to put in all your initial settings again (Switch type, local numbers and SPIDs).

The same symptoms will occur if the internal backup battery has died. Telos sell replacement batteries at a nominal cost. These are solder-in batteries, so if you’re not comfortable with soldering, this would require sending the unit back to Telos. EDnet sometimes can provide a loaner or rental unit in the interim.
(silver unit) if your XStream shows “ISDN MODEM” at the top of the LCD screen, chances are good you’ve received a telemarketer call on the XStream since you last used it. To get back to ISDN mode, change the Interface parameter in the TEL menu to “ISDN”. If this is a recurring issue for you, you can set the XStream to answer only ISDN calls. This parameter is also located in the TEL menu, and is called “auto ans”. If you use the XStream as a POTS coupler for plain old telephone calls, you’ll need to manually answer POTS calls.

No lock on the Zephyr (both versions), when all codec settings match. Both version of the zephyr have a known issue where. if the far end user is set to transmit audio from the AES/EBU input but is not presenting signal to the AES/EBU input, the near end will not lock.

The AUTO receive setting for the XStream can take up to 45 seconds to lock. Due to this EDnet recommend not using this setting.

(silver unit) If you do not lock to the far end codec and other trouble shooting options have been exhausted, try putting the unit in “ISDN loopmode” This bounces the far end’s data back to them off your ISDN card. If the far end gets their signal back, the there is no trouble with the data calls. In this instance, often you will solve by problem simply by toggling the XStream out of the loopmode setting.

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Mayah codecs:

The menu structure of the front panel controls is daunting. We recommend using a PC as a terminal to control the Mayah, put the PC and the Mayah on the same ethernet Local Area Network.
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APT codecs:

Pro Link:
1.  APT ProLink systems: boot up order is important to these older systems. From all-boxes-off, they should be booted in the following order: Audio section, wait for the VU meters to turn off, NT-1s (if off)—wait for them to stabilize into a slow-blink pattern, then the Pro Link.

2.  If you’re running version 1.11 software, and have a difficult time initializing the b1 positions to a Ready condition, you can force a Ready by hitting dial, enter, esc in quick succession. If you’re running 1.14 software, turn the ProLink off, leave it off for ~3 minutes, and then turn back on.

3.  One side is receiving a full-scale squeal: check that time code settings match on both sides of the connection.

4.  No audio is passing although ProLink’s display looks stable: check that both sides are in the same audio mode (either stereo or dual destination).
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1.  Check that the “algorithm” and “audio mode” settings match on both units.

2.  In standard aptx-16 mode, make sure the autosync parameter is set to “OFF”.

3.  For SMPTE enabled sessions, make sure both units are set to “TC L” and “AUX R”, although with time code being properly enabled.
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1.  With Ascend IMUX units (dialers), the call profile should be:
  • Call type = Bonding

  • Call mode = Mode 1

  • Base Ch Count = 4

  • Data SVC = 64kbps

  • Force 56 = no.

  • All other parameters (save for dial number) are optional

2.  Flickering lock lights: this is often indicative of a call type set to AIM instead of BONDING.

3.  Cabling: the three headed cable between components in a Dolby system are arranged with the 44 pin (Multiband) or 25 pin (Adtran) head to the dialer (port 1 for Multiband, RS530 for Adtran), 37 pin end with two cables coming out of it goes to the encoder (501, 523, 503), and the short jumper goes to the decoder (502, 524).

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Can EDnet provide bridging services between more than two studios?

  • Yes, we can provide two, three, and four way bridging services. Give us a call to discuss your specific needs, and we’ll be more than happy to help you out!

When is a bridge necessary? When going between incompatible systems. Incompatibilities include:

  • Source Connect to anything ISDN.

  • Dolby Fax to anything else. There is one not-particularly-useful exception: Dolby 503/524 in L2 mode can connect to some MPEG units over one B channel (64K) call, though the fidelitywill be "AM radio" quality.

  • APT to anything other than APT, Suprima, or Mayah.

  • Zephyrs, Suprimas, Road Warriors, Road Runners, Primas, CDQ2000/ CDQ2001, Mayah, Audio TX, and Prodys Prontos are mostly compatible between one another. The main exceptions are the Suprima/ Road Warrior/ Pronto family cannot connect to the CDQ2000/2001 family, and most codecs from differing manufacturers cannot connect to one another in AAC modes.
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