jspeedy,
I have seen the same thing with mine. It seems that when I pass a target or possible target there a 'null' for some time through the swing pattern and then through the return. It takes a few seconds or I will have to "wait" or possibly change hunting from 'coin and jewelry' to 'all metal'... It is at this point that I return to the original hunting mode the unit seems to get back to normal hunting. I attribute some of this to the possiblity that I am over 'trash' since I have proceeded or assumed I clear the unit as above and dig down to find a deep pipe, plate or heay mixture of trash underground. I maight also say this is not constant, since there are times the multiple tones are erratic also, but does get into that "nulling lag"...
The sites I have looked at lately are heavily laden with 'knocked down' houses, cans and the like... Not a pretty site, but it is an area park now that is active with people. nice appearance above ground but looks like crap underground... hahaha ! At any rate, this 'delayed tonal threshold loss' or "extended NULL" has not caused me to think the Safari is having a problem. Reason I say this is I have a "new camo" machine also and last weekend was comparing notes and depth. The confirmation of digging and "camo" signal were quite equal, leaving only the question of reset time lagging in the Safari. By that I mean it appeared to take a several seconds to clear the "swing pattern' on the Safari, where as the 'camo' unit was faster.
To further see what I was measuring in terms of 'Machines'... I have a "V" and it was a little slow on some targets, lag time from a "nulling' also in this area... Same digs, and appeared same effort related to the Safari. Not gonna try to attibute this to 'multi-Freq' issues but all machines had the same size coil 'relatively the stock'' and performed well where I was.
I just got my Safari two (2) weeks ago and I am learning it and must say I am liking it.. I moved to a new location after the above area was looked over for a couple of hours, to an 1880 school area where dirt and other debri was underground as a result of new additions, changes to play areas, and the like. All of the machines did the same thing when the sub-surface targets were "looking the same".. By that I mean old underground pipe, iron plates and the usual Vieenie Weeiiinee cans from construction... hahaha...
For the most part I did find a 1929 King George the Fifth 'one penny' coin with the safari at that school. If you are familiar with the length of a Garrett Pin Pointer, and adding four (4) inches above the battery cap to the surface.... there it was! The safari found it, and I took a picture of the Pin Pointer in the hole. I have a friend who has been plugging me to try a ML and I bought the Safari. Took the picture bacause the coin was "balls accurate in the bottom of that hole... Pleased I was DEAD-ON PINPOINT with the Safari!
Hope this helps because I do see what you are explaining, but only sharing what I see. My friend says my patience is longer than his, becasue I do analyze and dig, longer than he does... I will try to post that picture later.
As far as temperature excursions or being relative to the operation of the machines, seems 'moot' at this point for me. My Safari, Camo Unit, Silver Umax and my V stay in my van I travel in. I travel all over the South right now, and have done the same thing for a while thru the North East. Last weekend was 50 early in the morning and worked thru 67 degrees by the afternoon... My machines are in a "clothes hanging rack' next to the roof, 90 percent of the year, going where I go, and never had a problem. The Safari will get the same treatment as I go...LOL All of my machines a "have a place and time" for where I might be...
Hope it helps and I know it might not have helped with a good answer, but I feel I see what you are experiencing, and great hunting days for ya'...
asanaman
